diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
index 08a8479678002..9351caa7bc214 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
@@ -403,7 +403,7 @@ public function get_item( $request ) {
 			return $revision;
 		}
 
-		if ( $parent->ID !== $revision->post_parent ) {
+		if ( (int) $parent->ID !== (int) $revision->post_parent ) {
 			return new WP_Error(
 				'rest_post_invalid_parent',
 				/* translators: %s: A post revision id. */