How to display a list of posts in same child category as current post

I just figured this one out by modifying the first foreach statement.

$post_id = get_the_ID();
$cat_ids = array();
$categories = get_the_category();

 if ( $categories && !is_wp_error( $categories ) ) {

foreach( $categories as $category ) {
        if( 0 == $category->parent )
            {
             continue;
       }else{
              array_push( $cat_ids, $category->term_id ); 
            }
            $current_post_type = get_post_type( $post_id );

         $args = array(
            'category__in' => $cat_ids,
            'post_type' => $current_post_type,
            'posts_per_page' => '5',
            'post__not_in' => array( $post_id )
           );