diff --git a/packages/@aws-cdk/core/lib/stack-synthesizers/_shared.ts b/packages/@aws-cdk/core/lib/stack-synthesizers/_shared.ts
index 91251259c111d..f0cc2d548fd81 100644
--- a/packages/@aws-cdk/core/lib/stack-synthesizers/_shared.ts
+++ b/packages/@aws-cdk/core/lib/stack-synthesizers/_shared.ts
@@ -95,7 +95,7 @@ function collectStackMetadata(stack: Stack) {
   }
 
   function findParentStack(node: IConstruct): Stack | undefined {
-    if (node instanceof Stack && node.nestedStackParent === undefined) {
+    if (Stack.isStack(node) && node.nestedStackParent === undefined) {
       return node;
     }
 
@@ -183,4 +183,4 @@ export function stackTemplateFileAsset(stack: Stack, session: ISynthesisSession)
     packaging: FileAssetPackaging.FILE,
     sourceHash,
   };
-}
\ No newline at end of file
+}