diff --git a/wp-includes/template-functions-category.php b/wp-includes/template-functions-category.php
index 7cc72acebf..50e256604e 100644
--- a/wp-includes/template-functions-category.php
+++ b/wp-includes/template-functions-category.php
@@ -123,16 +123,20 @@ function get_category_parents($id, $link = FALSE, $separator = '/', $nicename =
 }
 
 function get_category_children($id, $before = '/', $after = '') {
-    global $cache_categories;
-    $c_cache = $cache_categories; // Can't do recursive foreach on a global, have to make a copy
-    $chain = '';
-    foreach ($c_cache as $category){
-        if ($category->category_parent == $id){
-            $chain .= $before.$category->cat_ID.$after;
-            $chain .= get_category_children($category->cat_ID, $before, $after);
-        }
-    }
-    return $chain;
+	global $cache_categories;
+
+	if ( ! isset($cache_categories))
+		update_category_cache();
+		
+	$c_cache = $cache_categories; // Can't do recursive foreach on a global, have to make a copy
+	$chain = '';
+	foreach ($c_cache as $category){
+		if ($category->category_parent == $id){
+			$chain .= $before.$category->cat_ID.$after;
+			$chain .= get_category_children($category->cat_ID, $before, $after);
+		}
+	}
+	return $chain;
 }
 
 // Deprecated.