diff --git a/api/src/category.repository.ts b/api/src/category.repository.ts
index 3afac7b..c0e3437 100644
--- a/api/src/category.repository.ts
+++ b/api/src/category.repository.ts
@@ -14,14 +14,15 @@ export class CategoryRepository {
      * Finds all descendants of a given path (including the path itself).
      * Uses the ltree operator <@ (is-descendant-of).
      */
-    async findAllDescendants(parentPath: string): Promise<CategoryNode[]> {
+    async findAllDescendants(parentPath: string, userId: number): Promise<CategoryNode[]> {
         const query = `
       SELECT id, name, path 
       FROM categories 
       WHERE path <@ $1::ltree
+        AND user_id = $2 --
       ORDER BY path ASC;
     `;
-        const result = await this.db.query(query, [parentPath]);
+        const result = await this.db.query(query, [parentPath, userId]);
         return result.rows;
     }