public function Pages()
    {
        $pages = SiteTree::get();
        $types = $this->PageTypes->getValue();
        if (count($types)) {
            $pages = $pages->filter('ClassName', $types);
        }

        $parents = $this->PageParents()->column('ID');
        if (count($parents)) {
            $pages = $pages->filter('ParentID', $parents);
        }

        return $pages;
    }