diff --git a/src/routes/portal.ts b/src/routes/portal.ts
index a4c2b87..651c5e2 100644
--- a/src/routes/portal.ts
+++ b/src/routes/portal.ts
@@ -149,9 +149,89 @@ portalRouter.get("/pets", async (c) => {
   const clientId = c.get("portalClientId");
 
   const clientPets = await db.select().from(pets).where(eq(pets.clientId, clientId));
-  return c.json(clientPets.map(p => ({ id: p.id, name: p.name, breed: p.breed, weight: p.weightKg, birthDate: p.dateOfBirth, photoUrl: p.photoKey, notes: p.groomingNotes })));
+  return c.json(clientPets.map(p => ({
+    id: p.id,
+    name: p.name,
+    species: p.species,
+    breed: p.breed,
+    weightKg: p.weightKg ? Number(p.weightKg) : null,
+    dateOfBirth: p.dateOfBirth ? new Date(p.dateOfBirth).toISOString() : null,
+    healthAlerts: p.healthAlerts,
+    groomingNotes: p.groomingNotes,
+    cutStyle: p.cutStyle,
+    shampooPreference: p.shampooPreference,
+    specialCareNotes: p.specialCareNotes,
+    coatType: p.coatType,
+    petSizeCategory: p.petSizeCategory,
+    photoKey: p.photoKey,
+    photoUploadedAt: p.photoUploadedAt ? new Date(p.photoUploadedAt).toISOString() : null,
+    customFields: p.customFields,
+  })));
 });
 
+const portalPetUpdateSchema = z.object({
+  name: z.string().min(1).max(200).optional(),
+  species: z.string().min(1).max(100).optional(),
+  breed: z.string().max(200).optional().nullable(),
+  weightKg: z.number().positive().optional().nullable(),
+  dateOfBirth: z.string().datetime().optional().nullable(),
+  healthAlerts: z.string().max(2000).optional().nullable(),
+  groomingNotes: z.string().max(2000).optional().nullable(),
+  cutStyle: z.string().max(500).optional().nullable(),
+  shampooPreference: z.string().max(500).optional().nullable(),
+  specialCareNotes: z.string().max(2000).optional().nullable(),
+  coatType: z.enum(["smooth", "double", "wire", "curly", "long", "hairless"]).optional().nullable(),
+  petSizeCategory: z.enum(["small", "medium", "large", "xlarge"]).optional().nullable(),
+  customFields: z.record(z.string(), z.string()).optional(),
+});
+
+portalRouter.patch("/pets/:id",
+  zValidator("json", portalPetUpdateSchema),
+  async (c) => {
+    const db = getDb();
+    const petId = c.req.param("id");
+    const clientId = c.get("portalClientId");
+    const body = c.req.valid("json");
+
+    const [existing] = await db.select().from(pets).where(eq(pets.id, petId)).limit(1);
+    if (!existing) return c.json({ error: "Not found" }, 404);
+    if (existing.clientId !== clientId) return c.json({ error: "Forbidden" }, 403);
+
+    const { weightKg, dateOfBirth, ...rest } = body;
+    const [updated] = await db
+      .update(pets)
+      .set({
+        ...rest,
+        weightKg: weightKg != null ? String(weightKg) : undefined,
+        dateOfBirth: dateOfBirth != null ? new Date(dateOfBirth) : undefined,
+        updatedAt: new Date(),
+      })
+      .where(eq(pets.id, petId))
+      .returning();
+
+    if (!updated) return c.json({ error: "Not found" }, 404);
+
+    return c.json({
+      id: updated.id,
+      name: updated.name,
+      species: updated.species,
+      breed: updated.breed,
+      weightKg: updated.weightKg ? Number(updated.weightKg) : null,
+      dateOfBirth: updated.dateOfBirth ? new Date(updated.dateOfBirth).toISOString() : null,
+      healthAlerts: updated.healthAlerts,
+      groomingNotes: updated.groomingNotes,
+      cutStyle: updated.cutStyle,
+      shampooPreference: updated.shampooPreference,
+      specialCareNotes: updated.specialCareNotes,
+      coatType: updated.coatType,
+      petSizeCategory: updated.petSizeCategory,
+      photoKey: updated.photoKey,
+      photoUploadedAt: updated.photoUploadedAt ? new Date(updated.photoUploadedAt).toISOString() : null,
+      customFields: updated.customFields,
+    });
+  }
+);
+
 portalRouter.get("/invoices", async (c) => {
   const db = getDb();
   const clientId = c.get("portalClientId");