Wordpress - Get children posts of parent post using Types plugin

I am working on a WordPress theme,I managed to create post relationships using Types plugin I created a tutorials CPT as parent and chapters CPT as child

I managed to display the child posts of the parent using

$child_posts = types_child_posts("chapters");

But now I am struggled at displaying the children list on the child pages, I mean when I am on a single chapter I need to display a list of the other chapters within the same parent

I managed to get the parent post id using Types API

$parent_id = wpcf_pr_post_get_belongs(get_the_ID(), 'tutorials');

But I can't find a way to use the id in the chapter pages to get an array of other chapters in this tutorial

What I Have Tried

• using WP_Query();
• using $child_posts =get_posts($childargs);
• using get_posts();

but all of the didn't do it unfortunately

Any help will be appreciated.

via Chebli Mohamed