How to order posts by their dates???

Hi, I want related posts order by date. How to do it?
I found a code below maybe cause the result:

/* Get posts by their IDs */
if ( !is_array( $random_posts ) || count( $random_posts ) < 1 ) {
return $this->finish_process( $output, $debug . 'No posts matching relationships criteria;', $time );
		}
$posts_in = array();
foreach ($random_posts as $random_post)
	$posts_in[] = $random_post->ID;
$query = "SELECT ID, post_content, post_excerpt, post_title FROM $wpdb->posts WHERE ID IN ('". implode( "', '", $posts_in ) . "')";
$posts = $wpdb->get_results( $query );
if ( ! ( is_array( $posts ) && count( $posts ) > 0 ) ) { // no posts
	$debug .= 'No posts found;';
	return $this->finish_process( $output, $debug, $time );
}
else
	$debug .= 'Found ' . count( $posts ) . ' posts;';

and I want the current post show up on list, too.
Thx!

https://www.ads-software.com/extend/plugins/related-posts-thumbnails/