List pages only if subpages exist

[KHCreative]

OK, after much trial and error, I figured it out. I'll post my code here so that someone less may be able to benefit from it some day.

PHP Code:

/*-----------------------------------------
Check if a page has any children / subpages
-----------------------------------------*/
 
function has_children(){
 global $post;
 
 if( ($post->post_parent == 0 && wp_list_pages('title_li=&child_of='.$post->ID.'&echo=0'))
 ||
 ($post->post_parent > 0 && wp_list_pages('title_li=&child_of='.$post->post_parent.'&echo=0'))
 ){
 return true;
 } else {
 return false;
 }
}
   
 if(!function_exists('get_post_top_ancestor_id')){
/**
 * Gets the id of the topmost ancestor of the current page. Returns the current
 * page's id if there is no parent.
 * 
 * @uses object $post
 * @return int 
 */
function get_post_top_ancestor_id(){
    global $post;
    
    if($post->post_parent){
        $ancestors = array_reverse(get_post_ancestors($page->ID));
        return $ancestors[0];
    }
    
    return $post->ID;
}}


add_action ('genesis_before_post_title', 'subpage_nav');
    function subpage_nav(){
    
        if ( is_page() && has_children($post->ID) ) {
        
        echo '<div id="pagenav">' . '<ul class="clearfix">';
        wp_list_pages( array('title_li'=>'','include'=>get_post_top_ancestor_id()) );
        wp_list_pages( array('title_li'=>'','depth'=>1,'child_of'=>get_post_top_ancestor_id()) );
        echo '</ul>' . '</div>';    
       }
   
   else{
           }

    }