WordPress - Get all child of parent page

index.php

<?php
$page_parent = get_page_by_path( 'page-parent-slug' ); // GET PAGE BY SLUG
$page_childs = get_pages( array( 
	'parent' => $page_parent->ID //GET CHILDS	
) );		
print_r( $page_childs );

/*
Array
(
    [0] => WP_Post Object
        (
            [ID] => 975
            [post_author] => 1
            [post_date] => 2017-02-02 14:22:00
            [post_date_gmt] => 2017-02-02 16:22:00
            [post_content] => [gallery size="full" ids="976,977,978,979,980,981,982,983,984,985,986"]
            [post_title] => Title
            [post_excerpt] => 
            [post_status] => publish
            [comment_status] => closed
            [ping_status] => closed
            [post_password] => 
            [post_name] => title
            [to_ping] => 
            [pinged] => 
            [post_modified] => 2017-02-02 14:22:00
            [post_modified_gmt] => 2017-02-02 16:22:00
            [post_content_filtered] => 
            [post_parent] => 548
            [guid] => http://site.com/?page_id=975
            [menu_order] => 2
            [post_type] => page
            [post_mime_type] => 
            [comment_count] => 0
            [filter] => raw
        )
)
*/