diff --git a/inputfiles/overridingTypes.jsonc b/inputfiles/overridingTypes.jsonc
index 756c85010..05ddf2334 100644
--- a/inputfiles/overridingTypes.jsonc
+++ b/inputfiles/overridingTypes.jsonc
@@ -19,12 +19,6 @@
                     }
                 }
             },
-            "ChildNode": {
-                "extends": "Node"
-            },
-            "ParentNode": {
-                "extends": "Node"
-            },
             "Animatable": {
                 "methods": {
                     "method": {
diff --git a/inputfiles/patches/child-parent-node.kdl b/inputfiles/patches/child-parent-node.kdl
new file mode 100644
index 000000000..63bf8de68
--- /dev/null
+++ b/inputfiles/patches/child-parent-node.kdl
@@ -0,0 +1,3 @@
+// ChildNode and ParentNode are actually defined as mixins, but because of their names they have historically been used as a sub-interface of Node.
+interface-mixin ChildNode extends=Node
+interface-mixin ParentNode extends=Node
diff --git a/src/build/patches.ts b/src/build/patches.ts
index 50a105a95..de5cee7f4 100644
--- a/src/build/patches.ts
+++ b/src/build/patches.ts
@@ -92,11 +92,15 @@ function handleMixin(node: Node): DeepPartial<Interface> {
     }
   }
 
-  return {
+  const result = {
     name,
     events: { event },
     properties: { property },
   } as DeepPartial<Interface>;
+  if (node.properties.extends) {
+    result.extends = node.properties.extends as string;
+  }
+  return result;
 }
 
 /**