Displaying parent page on child page list - php

Question

I have a script that is displaying child page list on parent page and a list o child pages without the current child page.
I would like to add the parent page on child pages, but I don't know how to achieve it. Could you please help me out?
This is my code:
if ('page-parent') {
echo '<h3>See also</h3>';
// if we are on a parent page set the $parent variable to current post id
// otherwise set $parent variable to current post parent
$parent = $post->post_parent == 0 ? $post->ID : $post->post_parent;
// if we use current post parent as $parent, exclude the current page
$exclude = $parent == $post->post_parent ? $post->ID : false;
// get all the children
$args = array( 'parent' => $parent, 'sort_column' => 'menu_order' );
if ( $exclude ) $args['exclude'] = $exclude;
$child_pages = get_pages($args);
// show only if there are children
if ( ! empty($child_pages) ) {
global $post;
foreach ( $child_pages as $post ) { setup_postdata( $post );
?>
<div class="child-thumb">
<?php the_title(); ?>
</div>
<?php
}
wp_reset_postdata();
}
}

Answer 1

You need to use 'child_of' argument instead of 'parent'. 'parent' in get_pages means to fetch or not to fetch parental pages.
But your case needs to fetch children of given page.
So you must use
$args = array( 'child_of' => $parent,
'sort_column' => 'menu_order' );
To display one single parent page above children, you can use get_post function:
if ($post->post_parent>0){
$parent_page=get_post($post->post_parent);
echo '<div>'.$parent_page->post_title.'</div>';
}
if ( ! empty($child_pages) ) {
///and so on...
For more information: https://codex.wordpress.org/Function_Reference/get_pages