Wordpress list pages from parent - wordpress

Question

I need help listing all pages when on a third level (grandchild) Page.
E.g I have Page 1(grandparent) Page 2(Parent) Page 3(Child)
I need to show all these pages listed the same on all three pages such as:
Page1
Page2
Page3
I have successfully shown the right list of pages on page 1 and 2. (see below)
Can anyone please help
function widget($args, $instance) {
global $post;
extract( $args );
if($post->post_parent == 0) {
$title = ''.$post->post_title.'';
$id_to_query = $post->ID;
}
elseif($post->ancestors) {
$page = get_page($post->ancestors[0]);
$title = ''.$page->post_title.'';
$id_to_query = $post->ancestors[0];
} else {
$page = get_page($post->post_parent);
$title = ''.$page->post_title.'';
$id_to_query = $page->ID;
}
$children = get_pages('post_type='.get_post_type().'&child_of='.$id_to_query);
if(empty($children) || is_page( array(17,125) ) ) return; // excludes contact us etc...
wp_reset_query();
$widget_title = $title;
echo $before_widget;
echo $before_title . $widget_title . $after_title; ?>
<ul>
<?php wp_list_pages('title_li=&post_type='.get_post_type().'&child_of='.$id_to_query); ?>
</ul>
<?php
echo $after_widget;
wp_reset_postdata();

Answer 1

Try getting the top ancestor id with $topid = get_top_ancestor($postid); then using the arguement 'child_of' => $topid and be mindful of your depth
Full example:
<?php
$postid = get_the_ID();
$topid = get_top_ancestor($postid);
$args = array(
'depth' => 2,
'show_date' => '',
'date_format' => get_option('date_format'),
'child_of' => $topid,
'exclude' => '',
'include' => '',
'echo' => 1,
'authors' => '',
'sort_order' => 'ASC',
'link_before' => '',
'link_after' => '',
'walker' => '',
'post_type' => 'page',
'post_status' => 'publish'
); ?>
<ul><?php wp_list_pages( $args ); ?></ul>
Something for you to work on [Untested]:
function widget($args, $instance) {
global $post;
$postid = get_the_ID();
$topid = get_top_ancestor($postid);
$args = array(
'depth' => 2,
'show_date' => '',
'date_format' => get_option('date_format'),
'child_of' => $topid,
'exclude' => '',
'include' => '',
'echo' => 1,
'authors' => '',
'sort_order' => 'ASC',
'link_before' => '',
'link_after' => '',
'walker' => '',
'post_type' => 'page',
'post_status' => 'publish'
);
// if(empty($children) || is_page( array(17,125) ) ) return; // excludes contact us etc...
// wp_reset_query();
$widget_title = $title;
echo $before_widget;
echo $before_title . $widget_title . $after_title; ?>
<ul>
<?php wp_list_pages( $args ); ?>
</ul>
<?php
echo $after_widget;
wp_reset_postdata();
}