diff --git a/packages/gatsby/index.d.ts b/packages/gatsby/index.d.ts
index fda7fcd8ad8b6..5bf3f0c6c23c8 100644
--- a/packages/gatsby/index.d.ts
+++ b/packages/gatsby/index.d.ts
@@ -202,7 +202,7 @@ export interface SlicePlaceholderProps {
   alias: string
   allowEmpty?: boolean
   children?: React.ReactNode
-  [key: string]: SerializableProps
+  [key: string]: SerializableProps | React.ReactNode
 }
 
 /**