Index: src/wp-includes/taxonomy.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
--- a/src/wp-includes/taxonomy.php	(revision 189a047cb8a5a99c752afc742eb71f2653fa65c5)
+++ b/src/wp-includes/taxonomy.php	(date 1650022403004)
@@ -1556,6 +1556,11 @@
 		if ( 0 === $term ) {
 			return 0;
 		}
+
+		if ( ! empty( $taxonomy ) && is_numeric( $parent ) ) {
+			$defaults['parent'] = (int) $parent;
+		}
+
 		$args  = wp_parse_args( array( 'include' => array( $term ) ), $defaults );
 		$terms = get_terms( $args );
 	} else {