Get Child and Grandchild Pages in WordPress

This tutorial provides code snippets for pulling all descendants of the current Page including grandchild Pages in WordPress.

Given the above Pages structure, when Page A is being viewed:

Unordered List

<ul>
    <?php
    wp_list_pages( array(
        'title_li'    => '',
        'child_of'    => get_the_ID(),
    ) );
    ?>
</ul>

IDs Array – Method 1

<?php

$child_pages = get_pages(
  array(
	'child_of' => get_the_ID(),
	)
);

$child_pages_ids = wp_list_pluck( $child_pages, 'ID' );

echo '<pre>' . print_r( $child_pages_ids, true ) . '</pre>';

?>

IDs Array – Method 2

<?php

$child_pages_objects = get_page_children( get_the_ID(), get_pages() );

$child_pages_ids = wp_list_pluck( $child_pages_objects, 'ID' );

echo '<pre>' . print_r( $child_pages_ids, true ) . '</pre>';

?>

References