diff --git a/messages/de.json b/messages/de.json
index 110a13f..d984dc6 100644
--- a/messages/de.json
+++ b/messages/de.json
@@ -64,6 +64,8 @@
     "namePlaceholder": "Name eingeben",
     "nameRequired": "Dieses Feld ist erforderlich.",
     "nameMaxLength": "Der Name darf maximal 30 Zeichen lang sein.",
+    "nickname": "Rufname / Spitzname (optional)",
+    "nicknamePlaceholder": "z. B. Rexi",
     "species": "Tierart",
     "selectSpecies": "Tierart auswählen",
     "speciesRequired": "Bitte wähle eine Tierart aus.",
diff --git a/messages/en.json b/messages/en.json
index 06c21bd..6e1377c 100644
--- a/messages/en.json
+++ b/messages/en.json
@@ -64,6 +64,8 @@
     "namePlaceholder": "Enter pet name",
     "nameRequired": "This field is required.",
     "nameMaxLength": "Pet name must be 30 characters or fewer.",
+    "nickname": "Nickname (optional)",
+    "nicknamePlaceholder": "e.g. Rexy",
     "species": "Species",
     "selectSpecies": "Select species",
     "speciesRequired": "Please select a species.",
diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index 5be9fe2..c26e58b 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -147,6 +147,7 @@ model Pet {
   breed         Breed?   @relation(fields: [breedId], references: [id])
   breedId       String?
   name          String
+  nickname      String?  @db.VarChar(30) // Rufname/Spitzname; shown after the real name, e.g. "Rex (Rexi)" — see src/lib/pet-display-name.ts
   bio           String?
   adoptionStory String?
   avatarKey     String? // Supabase Storage object key, NOT a full URL
diff --git a/src/app/(app)/pets/[petId]/edit/page.tsx b/src/app/(app)/pets/[petId]/edit/page.tsx
index 1d4b497..5af1d05 100644
--- a/src/app/(app)/pets/[petId]/edit/page.tsx
+++ b/src/app/(app)/pets/[petId]/edit/page.tsx
@@ -134,6 +134,7 @@ export default function EditPetPage() {
         initialAvatarKey={pet.avatarKey ?? null}
         initialValues={{
           name: pet.name,
+          nickname: pet.nickname ?? null,
           speciesId: pet.speciesId,
           breedId: pet.breedId ?? null,
           bio: pet.bio ?? null,
diff --git a/src/app/(app)/pets/[petId]/page.tsx b/src/app/(app)/pets/[petId]/page.tsx
index 5b9b0de..adb9f43 100644
--- a/src/app/(app)/pets/[petId]/page.tsx
+++ b/src/app/(app)/pets/[petId]/page.tsx
@@ -1,4 +1,5 @@
 import { notFound } from "next/navigation";
+import { formatPetName } from "@/lib/pet-display-name";
 import Link from "next/link";
 import { currentUser } from "@clerk/nextjs/server";
 import { getTranslations } from "next-intl/server";
@@ -71,7 +72,7 @@ export default async function PetProfilePage({ params }: PageProps) {
         />
 
         <h1 className="flex items-center gap-1.5 text-xl font-semibold text-center">
-          {pet.name}
+          {formatPetName(pet)}
           {pet.isVerified && (
             <BadgeCheck
               className="h-4 w-4 fill-blue-500 text-background"
@@ -136,7 +137,7 @@ export default async function PetProfilePage({ params }: PageProps) {
       </div>
 
       {/* ProfileActions: Follow + Message + options menu (client component) */}
-      <ProfileActions petId={pet.id} petName={pet.name} ownerId={pet.ownerId} />
+      <ProfileActions petId={pet.id} petName={formatPetName(pet)} ownerId={pet.ownerId} />
 
       {pet.bio && (
         <>
diff --git a/src/app/p/[secret]/users/page.tsx b/src/app/p/[secret]/users/page.tsx
index b8a6930..1dd09df 100644
--- a/src/app/p/[secret]/users/page.tsx
+++ b/src/app/p/[secret]/users/page.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { useState } from "react";
+import { formatPetName } from "@/lib/pet-display-name";
 import { useRouter, useParams } from "next/navigation";
 import { toast } from "sonner";
 import { useInfiniteQuery, useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
@@ -122,7 +123,7 @@ export default function AdminUsersPage() {
     trpc.admin.setPetVerified.mutationOptions({
       onSuccess: (pet) => {
         void qc.invalidateQueries({ queryKey: trpc.admin.listUsers.queryKey() });
-        toast.success(pet.isVerified ? `${pet.name} verified.` : `${pet.name} un-verified.`);
+        toast.success(pet.isVerified ? `${formatPetName(pet)} verified.` : `${formatPetName(pet)} un-verified.`);
       },
       onError: (err) => {
         toast.error(`Verification failed: ${err.message}`);
@@ -274,7 +275,7 @@ export default function AdminUsersPage() {
                             : "border-zinc-700 text-zinc-400 hover:border-zinc-600"
                         }`}
                       >
-                        {pet.name}
+                        {formatPetName(pet)}
                         <BadgeCheck
                           className={`h-3 w-3 ${pet.isVerified ? "fill-blue-400 text-zinc-950" : ""}`}
                         />
diff --git a/src/components/feed/MilestoneCard.tsx b/src/components/feed/MilestoneCard.tsx
index 11eb462..1f50b71 100644
--- a/src/components/feed/MilestoneCard.tsx
+++ b/src/components/feed/MilestoneCard.tsx
@@ -3,6 +3,7 @@
 import type { MilestoneType } from "@prisma/client";
 import { MILESTONE_META } from "@/lib/milestone-meta";
 import { getAvatarUrl } from "@/lib/avatar-url";
+import { formatPetName } from "@/lib/pet-display-name";
 import { getMediaUrl } from "@/lib/media-url";
 import { BlurImage } from "@/components/ui/blur-image";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
@@ -60,7 +61,7 @@ export function MilestoneCard({ post }: MilestoneCardProps) {
         </Avatar>
         <div className="flex-1 min-w-0">
           <p className="text-base font-semibold text-foreground leading-tight truncate">
-            {pet.name}
+            {formatPetName(pet)}
           </p>
           <p className="text-xs text-muted-foreground">{formatDate(post.createdAt)}</p>
         </div>
diff --git a/src/components/feed/PostCard.tsx b/src/components/feed/PostCard.tsx
index e062044..7290fa7 100644
--- a/src/components/feed/PostCard.tsx
+++ b/src/components/feed/PostCard.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { useState, useEffect, useCallback, memo } from "react";
+import { formatPetName } from "@/lib/pet-display-name";
 import { MoreHorizontal, MessageCircle, Sparkles, BadgeCheck } from "lucide-react";
 import { toast } from "sonner";
 import { useMutation } from "@tanstack/react-query";
@@ -246,7 +247,7 @@ function PostCardImpl({ post, onDeleted, variant = "feed" }: PostCardProps) {
 
           <div className="flex-1 min-w-0">
             <p className="flex items-center gap-1 text-base font-semibold text-foreground leading-tight truncate">
-              {pet.name}
+              {formatPetName(pet)}
               {pet.isVerified && (
                 <BadgeCheck
                   className="h-3.5 w-3.5 shrink-0 fill-blue-500 text-background"
@@ -551,7 +552,7 @@ function PostCardImpl({ post, onDeleted, variant = "feed" }: PostCardProps) {
           onOpenChange={setShowBlockDialog}
           blockerPetId={activePetId}
           blockedPetId={pet.id}
-          blockedPetName={pet.name}
+          blockedPetName={formatPetName(pet)}
         />
       )}
     </article>
diff --git a/src/components/feed/PostDetailDialog.tsx b/src/components/feed/PostDetailDialog.tsx
index 1a6c4ea..97f78f6 100644
--- a/src/components/feed/PostDetailDialog.tsx
+++ b/src/components/feed/PostDetailDialog.tsx
@@ -5,6 +5,7 @@ import { MoreHorizontal, Trash2, Loader2 } from "lucide-react";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { toast } from "sonner";
 import { useTRPC } from "@/trpc/client";
+import { formatPetName } from "@/lib/pet-display-name";
 import { useActivePet } from "@/context/ActivePetContext";
 import { Dialog, DialogContent } from "@/components/ui/dialog";
 import { Avatar, AvatarFallback } from "@/components/ui/avatar";
@@ -193,7 +194,7 @@ export function PostDetailDialog({ post, open, onClose, onDeleted }: PostDetailD
           <PetAvatar name={pet.name} avatarKey={pet.avatarKey} className="w-8 h-8" />
         </PawRing>
         <div className="flex-1 min-w-0">
-          <p className="text-sm font-semibold text-foreground leading-tight truncate">{pet.name}</p>
+          <p className="text-sm font-semibold text-foreground leading-tight truncate">{formatPetName(pet)}</p>
           <p className="text-xs text-muted-foreground">{formatRelativeTime(post.createdAt)}</p>
         </div>
       </Link>
@@ -560,7 +561,7 @@ export function PostDetailDialog({ post, open, onClose, onDeleted }: PostDetailD
           onOpenChange={setShowBlockDialog}
           blockerPetId={activePetId}
           blockedPetId={pet.id}
-          blockedPetName={pet.name}
+          blockedPetName={formatPetName(pet)}
         />
       )}
     </>
diff --git a/src/components/layout/MobileNav.tsx b/src/components/layout/MobileNav.tsx
index 8d19067..2bb8254 100644
--- a/src/components/layout/MobileNav.tsx
+++ b/src/components/layout/MobileNav.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { useState } from "react";
+import { formatPetName } from "@/lib/pet-display-name";
 import Link from "next/link";
 import { usePathname, useRouter } from "next/navigation";
 import {
@@ -106,7 +107,7 @@ export function MobileNav({ pets }: MobileNavProps) {
                 className="h-6 w-6 shrink-0"
               />
               <span className="font-medium text-foreground truncate max-w-[120px] flex items-center gap-1">
-                {activePet.name}
+                {formatPetName(activePet)}
                 {activePet.isVerified && (
                   <BadgeCheck className="h-3 w-3 shrink-0 fill-blue-500 text-background" />
                 )}
@@ -126,7 +127,7 @@ export function MobileNav({ pets }: MobileNavProps) {
                     className="h-6 w-6 shrink-0"
                   />
                   <span className="flex-1 text-sm truncate flex items-center gap-1">
-                    {pet.name}
+                    {formatPetName(pet)}
                     {pet.isVerified && (
                       <BadgeCheck className="h-3 w-3 shrink-0 fill-blue-500 text-background" />
                     )}
diff --git a/src/components/layout/Sidebar.tsx b/src/components/layout/Sidebar.tsx
index 97d1382..617bf7e 100644
--- a/src/components/layout/Sidebar.tsx
+++ b/src/components/layout/Sidebar.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { useState, useEffect } from "react";
+import { formatPetName } from "@/lib/pet-display-name";
 import Link from "next/link";
 import { usePathname, useRouter } from "next/navigation";
 import {
@@ -148,7 +149,7 @@ export function Sidebar({ pets }: SidebarProps) {
               {!collapsed && (
                 <>
                   <span className="text-sm font-medium text-foreground flex-1 truncate flex items-center gap-1">
-                    {activePet.name}
+                    {formatPetName(activePet)}
                     {activePet.isVerified && (
                       <BadgeCheck className="h-3.5 w-3.5 shrink-0 fill-blue-500 text-background" />
                     )}
@@ -170,7 +171,7 @@ export function Sidebar({ pets }: SidebarProps) {
                     className="h-6 w-6 shrink-0"
                   />
                   <span className="flex-1 text-sm truncate flex items-center gap-1">
-                    {pet.name}
+                    {formatPetName(pet)}
                     {pet.isVerified && (
                       <BadgeCheck className="h-3 w-3 shrink-0 fill-blue-500 text-background" />
                     )}
diff --git a/src/components/messages/MessageThread.tsx b/src/components/messages/MessageThread.tsx
index 197a9fb..3795619 100644
--- a/src/components/messages/MessageThread.tsx
+++ b/src/components/messages/MessageThread.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { useState, useEffect, useRef, useCallback } from "react";
+import { formatPetName } from "@/lib/pet-display-name";
 import { useRouter } from "next/navigation";
 import { ArrowLeft, Send, Loader2 } from "lucide-react";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
@@ -128,7 +129,7 @@ export function MessageThread({ conversationId, otherPet }: MessageThreadProps)
               {otherPet.name[0]?.toUpperCase() ?? "?"}
             </AvatarFallback>
           </Avatar>
-          <span className="text-sm font-semibold">{otherPet.name}</span>
+          <span className="text-sm font-semibold">{formatPetName(otherPet)}</span>
         </Link>
       </div>
 
@@ -148,7 +149,7 @@ export function MessageThread({ conversationId, otherPet }: MessageThreadProps)
                 {otherPet.name[0]?.toUpperCase() ?? "?"}
               </AvatarFallback>
             </Avatar>
-            <p className="text-sm font-medium mt-2">{otherPet.name}</p>
+            <p className="text-sm font-medium mt-2">{formatPetName(otherPet)}</p>
             <p className="text-xs">{t("empty")}</p>
           </div>
         )}
diff --git a/src/components/pet/PetForm.tsx b/src/components/pet/PetForm.tsx
index 3f91e0e..1904602 100644
--- a/src/components/pet/PetForm.tsx
+++ b/src/components/pet/PetForm.tsx
@@ -38,6 +38,11 @@ const petFormSchema = z.object({
     .string()
     .min(1, "This field is required.")
     .max(30, "Pet name must be 30 characters or fewer."),
+  nickname: z
+    .string()
+    .max(30, "Nickname must be 30 characters or fewer.")
+    .optional()
+    .nullable(),
   speciesId: z.string().min(1, "Please select a species."),
   breedId: z.string().nullable().optional(),
   bio: z
@@ -137,6 +142,7 @@ export function PetForm({
     resolver: zodResolver(petFormSchema),
     defaultValues: {
       name: initialValues?.name ?? "",
+      nickname: initialValues?.nickname ?? "",
       speciesId: initialValues?.speciesId ?? "",
       breedId: initialValues?.breedId ?? null,
       bio: initialValues?.bio ?? "",
@@ -154,6 +160,7 @@ export function PetForm({
     if (mode === "create") {
       createMutation.mutate({
         name: data.name,
+        nickname: data.nickname || undefined,
         speciesId: data.speciesId,
         breedId: data.breedId ?? undefined,
         bio: data.bio ?? undefined,
@@ -163,6 +170,7 @@ export function PetForm({
       updateMutation.mutate({
         petId: petId!,
         name: data.name,
+        nickname: data.nickname || null,
         breedId: data.breedId ?? null,
         bio: data.bio ?? null,
         adoptionStory: data.adoptionStory ?? null,
@@ -211,6 +219,21 @@ export function PetForm({
         )}
       </div>
 
+      {/* Nickname / Rufname — optional, shown after the real name everywhere, e.g. "Rex (Rexi)" */}
+      <div className="flex flex-col gap-1.5">
+        <Label htmlFor="pet-nickname">{t("nickname")}</Label>
+        <Input
+          id="pet-nickname"
+          maxLength={30}
+          placeholder={t("nicknamePlaceholder")}
+          aria-invalid={!!errors.nickname}
+          {...register("nickname")}
+        />
+        {errors.nickname && (
+          <p className="text-xs text-destructive">{errors.nickname.message}</p>
+        )}
+      </div>
+
       {/* Species selector — defer render until list loaded so SelectValue resolves names */}
       <div className="flex flex-col gap-1.5">
         <Label htmlFor="species">{t("species")}</Label>
diff --git a/src/lib/mention-helpers.ts b/src/lib/mention-helpers.ts
index 7eea178..4b79abc 100644
--- a/src/lib/mention-helpers.ts
+++ b/src/lib/mention-helpers.ts
@@ -31,7 +31,10 @@ export async function createMentionNotifications(
 
   const mentionedPets = await prisma.pet.findMany({
     where: {
-      name: { in: names, mode: "insensitive" },
+      OR: [
+        { name: { in: names, mode: "insensitive" } },
+        { nickname: { in: names, mode: "insensitive" } },
+      ],
       id: { not: actorPetId },
     },
     select: { id: true },
diff --git a/src/lib/pet-display-name.ts b/src/lib/pet-display-name.ts
new file mode 100644
index 0000000..2b2d6b0
--- /dev/null
+++ b/src/lib/pet-display-name.ts
@@ -0,0 +1,8 @@
+/**
+ * Formats a pet's display name: real name first, nickname/Rufname after
+ * in parentheses when set — e.g. "Rex (Rexi)". Same format everywhere,
+ * including the admin panel, per explicit product decision.
+ */
+export function formatPetName(pet: { name: string; nickname?: string | null }): string {
+  return pet.nickname ? `${pet.name} (${pet.nickname})` : pet.name;
+}
diff --git a/src/trpc/routers/admin.ts b/src/trpc/routers/admin.ts
index 2801b63..0fb3fdd 100644
--- a/src/trpc/routers/admin.ts
+++ b/src/trpc/routers/admin.ts
@@ -291,7 +291,7 @@ export const adminRouter = router({
             }
           : undefined,
         include: {
-          pet: { select: { id: true, name: true, avatarKey: true, ownerId: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true, ownerId: true } },
           images: { orderBy: { position: "asc" }, take: 1 },
           videoPost: { select: { muxPlaybackId: true } },
           milestone: true,
@@ -299,7 +299,7 @@ export const adminRouter = router({
             include: {
               originalPost: {
                 include: {
-                  pet: { select: { id: true, name: true } },
+                  pet: { select: { id: true, name: true, nickname: true } },
                   images: { orderBy: { position: "asc" }, take: 1 },
                   milestone: true,
                 },
@@ -557,7 +557,7 @@ export const adminRouter = router({
       await assertAdmin(ctx.prisma, ctx.userId);
       return ctx.prisma.comment.findMany({
         where: { postId: input.postId },
-        include: { pet: { select: { id: true, name: true, avatarKey: true } } },
+        include: { pet: { select: { id: true, name: true, nickname: true, avatarKey: true } } },
         orderBy: { createdAt: "asc" },
       });
     }),
@@ -632,7 +632,7 @@ export const adminRouter = router({
           ...(input.role !== "all" && input.role !== "none" ? { adminRole: { role: input.role } } : {}),
         },
         include: {
-          pets: { select: { id: true, name: true, avatarKey: true, isVerified: true }, take: 3 },
+          pets: { select: { id: true, name: true, nickname: true, avatarKey: true, isVerified: true }, take: 3 },
           ban: true,
           shadowban: true,
           adminRole: true,
@@ -864,6 +864,7 @@ export const adminRouter = router({
             select: {
               id: true,
               name: true,
+              nickname: true,
               avatarKey: true,
               isVerified: true,
               ownerId: true,
@@ -1060,8 +1061,8 @@ export const adminRouter = router({
     const convs = await ctx.prisma.conversation.findMany({
       where: { OR: [{ petAId: teamPet.id }, { petBId: teamPet.id }] },
       include: {
-        petA: { select: { id: true, name: true, avatarKey: true } },
-        petB: { select: { id: true, name: true, avatarKey: true } },
+        petA: { select: { id: true, name: true, nickname: true, avatarKey: true } },
+        petB: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         messages: { orderBy: { createdAt: "desc" }, take: 1 },
         _count: {
           select: { messages: { where: { senderPetId: { not: teamPet.id }, readAt: null } } },
@@ -1095,7 +1096,7 @@ export const adminRouter = router({
         where: { conversationId: input.conversationId },
         orderBy: { createdAt: "asc" },
         take: 200,
-        include: { senderPet: { select: { id: true, name: true, avatarKey: true } } },
+        include: { senderPet: { select: { id: true, name: true, nickname: true, avatarKey: true } } },
       });
 
       // Fire-and-forget — any admin opening the thread marks it read for the whole team.
@@ -1198,7 +1199,7 @@ export const adminRouter = router({
 
     const reports = await ctx.prisma.report.findMany({
       include: {
-        reporter: { select: { id: true, name: true, avatarKey: true } },
+        reporter: { select: { id: true, name: true, nickname: true, avatarKey: true } },
       },
       orderBy: { createdAt: "desc" },
       take: 100,
@@ -1219,7 +1220,7 @@ export const adminRouter = router({
             createdAt: true,
             reactionCount: true,
             commentCount: true,
-            pet: { select: { id: true, name: true, avatarKey: true } },
+            pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
             images: {
               orderBy: { position: "asc" },
               take: 4,
@@ -1262,7 +1263,7 @@ export const adminRouter = router({
           type: true,
           createdAt: true,
           hiddenAt: true,
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           images: {
             orderBy: { position: "asc" },
             select: { storageKey: true, position: true, blurhash: true },
@@ -1271,7 +1272,7 @@ export const adminRouter = router({
             orderBy: { createdAt: "desc" },
             take: 200,
             select: {
-              pet: { select: { id: true, name: true, avatarKey: true } },
+              pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
             },
           },
         },
@@ -1511,7 +1512,7 @@ export const adminRouter = router({
     return ctx.prisma.adminRole.findMany({
       include: {
         owner: {
-          include: { pets: { select: { name: true, avatarKey: true }, take: 1 } },
+          include: { pets: { select: { name: true, nickname: true, avatarKey: true }, take: 1 } },
         },
       },
       orderBy: { grantedAt: "desc" },
@@ -1594,7 +1595,7 @@ export const adminRouter = router({
       const owners = moderatorIds.length > 0
         ? await ctx.prisma.owner.findMany({
             where: { id: { in: moderatorIds } },
-            select: { id: true, pets: { select: { name: true }, take: 1 } },
+            select: { id: true, pets: { select: { name: true, nickname: true }, take: 1 } },
           })
         : [];
       const nameByOwnerId = new Map(owners.map((o) => [o.id, o.pets[0]?.name ?? null]));
@@ -1630,7 +1631,7 @@ export const adminRouter = router({
         orderBy: { createdAt: "desc" },
         take: input.limit,
         include: {
-          issuedBy: { select: { id: true, pets: { select: { name: true }, take: 1 } } },
+          issuedBy: { select: { id: true, pets: { select: { name: true, nickname: true }, take: 1 } } },
         },
       });
     }),
diff --git a/src/trpc/routers/ads.ts b/src/trpc/routers/ads.ts
index e6d7681..bcc1060 100644
--- a/src/trpc/routers/ads.ts
+++ b/src/trpc/routers/ads.ts
@@ -91,7 +91,7 @@ export const adsRouter = router({
       return ctx.prisma.adComment.findMany({
         where: { adId: input.adId },
         include: {
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
         orderBy: { createdAt: "asc" },
         take: 100,
@@ -113,7 +113,7 @@ export const adsRouter = router({
         ctx.prisma.adComment.create({
           data: { adId: input.adId, petId: input.petId, body: input.body },
           include: {
-            pet: { select: { id: true, name: true, avatarKey: true } },
+            pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           },
         }),
         ctx.prisma.advertisement.update({
diff --git a/src/trpc/routers/comments.ts b/src/trpc/routers/comments.ts
index 6d282e9..132ee93 100644
--- a/src/trpc/routers/comments.ts
+++ b/src/trpc/routers/comments.ts
@@ -27,7 +27,7 @@ export const commentsRouter = router({
             body: input.body,
           },
           include: {
-            pet: { select: { id: true, name: true, avatarKey: true } },
+            pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           },
         }),
         ctx.prisma.post.update({
@@ -77,7 +77,7 @@ export const commentsRouter = router({
         orderBy: { createdAt: "asc" },
         take: input.limit + 1,
         include: {
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
       });
 
diff --git a/src/trpc/routers/explore.ts b/src/trpc/routers/explore.ts
index adc83b5..ec0c33d 100644
--- a/src/trpc/routers/explore.ts
+++ b/src/trpc/routers/explore.ts
@@ -79,6 +79,7 @@ export const exploreRouter = router({
             select: {
               id: true,
               name: true,
+              nickname: true,
               avatarKey: true,
               isVerified: true,
               owner: { select: { sponsorSince: true, sponsorPeriodEnd: true } },
diff --git a/src/trpc/routers/feed.ts b/src/trpc/routers/feed.ts
index 63bb957..6794ff4 100644
--- a/src/trpc/routers/feed.ts
+++ b/src/trpc/routers/feed.ts
@@ -31,6 +31,7 @@ const postInclude = {
     select: {
       id: true,
       name: true,
+      nickname: true,
       avatarKey: true,
       isVerified: true,
       owner: { select: { sponsorSince: true, sponsorPeriodEnd: true } },
@@ -47,6 +48,7 @@ const postInclude = {
     select: {
       id: true,
       name: true,
+      nickname: true,
       avatarKey: true,
       isVerified: true,
       owner: { select: { sponsorSince: true, sponsorPeriodEnd: true } },
diff --git a/src/trpc/routers/follows.ts b/src/trpc/routers/follows.ts
index 2569fb5..123a76f 100644
--- a/src/trpc/routers/follows.ts
+++ b/src/trpc/routers/follows.ts
@@ -83,7 +83,7 @@ export const followsRouter = router({
           include: {
             images: { orderBy: { position: "asc" } },
             milestone: true,
-            pet: { select: { id: true, name: true, avatarKey: true } },
+            pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           },
         });
 
@@ -176,6 +176,7 @@ export const followsRouter = router({
             select: {
               id: true,
               name: true,
+              nickname: true,
               avatarKey: true,
               species: { select: { name: true, translations: { where: { locale: ctx.locale } } } },
             },
@@ -220,7 +221,7 @@ export const followsRouter = router({
           },
         },
         select: {
-          followee: { select: { id: true, name: true, avatarKey: true } },
+          followee: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
         orderBy: { createdAt: "desc" },
         take: 100,
@@ -253,6 +254,7 @@ export const followsRouter = router({
             select: {
               id: true,
               name: true,
+              nickname: true,
               avatarKey: true,
               species: { select: { name: true, translations: { where: { locale: ctx.locale } } } },
             },
diff --git a/src/trpc/routers/messages.ts b/src/trpc/routers/messages.ts
index 4a2437e..ab44bd2 100644
--- a/src/trpc/routers/messages.ts
+++ b/src/trpc/routers/messages.ts
@@ -50,8 +50,8 @@ export const conversationsRouter = router({
       const convs = await ctx.prisma.conversation.findMany({
         where: { OR: [{ petAId: input.petId }, { petBId: input.petId }] },
         include: {
-          petA: { select: { id: true, name: true, avatarKey: true } },
-          petB: { select: { id: true, name: true, avatarKey: true } },
+          petA: { select: { id: true, name: true, nickname: true, avatarKey: true } },
+          petB: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           messages: {
             orderBy: { createdAt: "desc" },
             take: 1,
@@ -188,7 +188,7 @@ export const messagesRouter = router({
         orderBy: { createdAt: "asc" },
         take: input.limit + 1,
         include: {
-          senderPet: { select: { id: true, name: true, avatarKey: true } },
+          senderPet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
       });
 
@@ -237,7 +237,7 @@ export const messagesRouter = router({
             senderPetId: input.senderPetId,
             body: input.body,
           },
-          include: { senderPet: { select: { id: true, name: true, avatarKey: true } } },
+          include: { senderPet: { select: { id: true, name: true, nickname: true, avatarKey: true } } },
         }),
         // Touch conversation updatedAt so inbox re-orders correctly
         ctx.prisma.conversation.update({
diff --git a/src/trpc/routers/milestones.ts b/src/trpc/routers/milestones.ts
index 5e65a5a..15a17d0 100644
--- a/src/trpc/routers/milestones.ts
+++ b/src/trpc/routers/milestones.ts
@@ -66,7 +66,7 @@ export const milestonesRouter = router({
         include: {
           images: { orderBy: { position: "asc" } },
           milestone: true,
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
       });
 
@@ -97,7 +97,7 @@ export const milestonesRouter = router({
         include: {
           milestone: true,
           images: { orderBy: { position: "asc" } },
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
         orderBy: { createdAt: "desc" },
         take: input.limit,
diff --git a/src/trpc/routers/notifications.ts b/src/trpc/routers/notifications.ts
index 5555574..b47b6d1 100644
--- a/src/trpc/routers/notifications.ts
+++ b/src/trpc/routers/notifications.ts
@@ -26,7 +26,7 @@ export const notificationsRouter = router({
         orderBy: { createdAt: "desc" },
         take: input.limit + 1,
         include: {
-          actorPet: { select: { id: true, name: true, avatarKey: true } },
+          actorPet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           post: { select: { id: true, petId: true, images: { take: 1, orderBy: { position: "asc" } } } },
           comment: { select: { id: true, body: true } },
         },
diff --git a/src/trpc/routers/pets.ts b/src/trpc/routers/pets.ts
index aeb52c7..b72eb10 100644
--- a/src/trpc/routers/pets.ts
+++ b/src/trpc/routers/pets.ts
@@ -17,6 +17,7 @@ export const petsRouter = router({
     .input(
       z.object({
         name: z.string().min(1).max(30),
+        nickname: z.string().max(30).optional(),
         speciesId: z.string().min(1),
         breedId: z.string().optional(),
         bio: z.string().max(150).optional(),
@@ -48,6 +49,7 @@ export const petsRouter = router({
         data: {
           ownerId: ctx.userId,
           name: input.name,
+          nickname: input.nickname ?? null,
           speciesId: input.speciesId,
           breedId: input.breedId ?? null,
           bio: input.bio ?? null,
@@ -145,6 +147,7 @@ export const petsRouter = router({
       z.object({
         petId: z.string().min(1),
         name: z.string().max(30).optional(),
+        nickname: z.string().max(30).optional().nullable(),
         bio: z.string().max(150).optional().nullable(),
         adoptionStory: z.string().max(500).optional().nullable(),
         breedId: z.string().optional().nullable(),
@@ -161,6 +164,7 @@ export const petsRouter = router({
       // Only update fields that were explicitly provided
       const updateData: Record<string, unknown> = {};
       if (data.name !== undefined) updateData.name = data.name;
+      if (data.nickname !== undefined) updateData.nickname = data.nickname;
       if (data.bio !== undefined) updateData.bio = data.bio;
       if (data.adoptionStory !== undefined)
         updateData.adoptionStory = data.adoptionStory;
diff --git a/src/trpc/routers/posts.ts b/src/trpc/routers/posts.ts
index 15c1645..13cf101 100644
--- a/src/trpc/routers/posts.ts
+++ b/src/trpc/routers/posts.ts
@@ -129,7 +129,7 @@ export const postsRouter = router({
         },
         include: {
           images: { orderBy: { position: "asc" } },
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           milestone: true,
         },
       });
@@ -197,7 +197,7 @@ export const postsRouter = router({
         data: { caption: input.caption },
         include: {
           images: { orderBy: { position: "asc" } },
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           milestone: true,
         },
       });
@@ -249,14 +249,14 @@ export const postsRouter = router({
         take: input.limit + 1,
         include: {
           images: { orderBy: { position: "asc" } },
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           milestone: true,
           videoPost: { select: { status: true, muxPlaybackId: true } },
           repost: {
             include: {
               originalPost: {
                 include: {
-                  pet: { select: { id: true, name: true, avatarKey: true } },
+                  pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
                   images: { orderBy: { position: "asc" } },
                   milestone: true,
                 },
@@ -291,14 +291,14 @@ export const postsRouter = router({
         },
         include: {
           images: { orderBy: { position: "asc" } },
-          pet: { select: { id: true, name: true, avatarKey: true } },
+          pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
           milestone: true,
           videoPost: { select: { status: true, muxPlaybackId: true } },
           repost: {
             include: {
               originalPost: {
                 include: {
-                  pet: { select: { id: true, name: true, avatarKey: true } },
+                  pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
                   images: { orderBy: { position: "asc" } },
                   milestone: true,
                 },
diff --git a/src/trpc/routers/search.ts b/src/trpc/routers/search.ts
index cd9ece2..2eb6d2b 100644
--- a/src/trpc/routers/search.ts
+++ b/src/trpc/routers/search.ts
@@ -20,6 +20,7 @@ export const searchRouter = router({
         where: {
           OR: [
             { name: { contains: input.query, mode: "insensitive" } },
+            { nickname: { contains: input.query, mode: "insensitive" } },
             { breed: { name: { contains: input.query, mode: "insensitive" } } },
           ],
           ...(input.cursor ? { id: { gt: input.cursor } } : {}),
@@ -84,7 +85,7 @@ export const searchRouter = router({
         include: {
           post: {
             include: {
-              pet: { select: { id: true, name: true, avatarKey: true } },
+              pet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
               images: { orderBy: { position: "asc" }, take: 1 },
             },
           },
diff --git a/src/trpc/routers/stories.ts b/src/trpc/routers/stories.ts
index 85c8646..95d1726 100644
--- a/src/trpc/routers/stories.ts
+++ b/src/trpc/routers/stories.ts
@@ -172,7 +172,7 @@ export const storiesRouter = router({
       return ctx.prisma.storyView.findMany({
         where: { storyId: input.storyId },
         include: {
-          viewerPet: { select: { id: true, name: true, avatarKey: true } },
+          viewerPet: { select: { id: true, name: true, nickname: true, avatarKey: true } },
         },
         orderBy: { viewedAt: "desc" },
         take: 200,