$childrens = get_children( array(
'post_parent' => id страницы родителя,
'post_type' => 'page',
'numberposts' => -1,
'post_status' => 'publish'
) );
ob_start();
blablabla
wp_editor();
blabla
$html = ob_get_contents();
ob_clean();
echo $html;
if(i === 1) $tags = get_the_tags(get_the_ID());
get_posts( array("tag__in" => array(tags[0]->term_id)) );