protected function isParentArchived()
    {
        if ($parentID = $this->ParentID) {
            /** @var SiteTree $parentPage */
            $parentPage = Versioned::get_latest_version(self::class, $parentID);
            if (!$parentPage || !$parentPage->isOnDraft()) {
                return true;
            }
        }
        return false;
    }