public static function get_category_children_visibility($categoryid) {
        global $DB;
        $category = \core_course_category::get($categoryid);
        $select = $DB->sql_like('path', ':path');
        $path = $category->path . '/%';

        $sql = "SELECT c.id, c.visible
                  FROM {course_categories} c
                 WHERE ".$select;
        $params = array('path' => $path);
        return $DB->get_records_sql($sql, $params);
    }