diff --git a/Gutenberg/check-inner-blocks.php b/Gutenberg/check-inner-blocks.php
index bedf6e2..cda258c 100644
--- a/Gutenberg/check-inner-blocks.php
+++ b/Gutenberg/check-inner-blocks.php
@@ -1,3 +1,4 @@
+$inner_blocks = $block->inner_blocks;
 foreach ( $inner_blocks as $block ) {
 		if ( 'core/post-featured-image' === $block->name ) {
 			return true;