How to List the direct Child or Children of the current Post of a Custom Post Type. The depth is set to 1 so it will only show the direct children and not the children’s children.
1, // How far to show, 2=shows child and grandchild 0=all
'child_of' => $post->ID, // Show Child of Current Post
'exclude' => '',
'include' => '',
'title_li' => '', // Do not Show a Title
'echo' => 1,
'authors' => '',
'sort_column' => 'menu_order, post_title',
'walker' => '',
'post_type' => 'custom_post_tpe_name', // Post Type Name
'post_status' => 'publish'