including template file for posts in sub categories

I have several posts that are under several sub categories of sub categories (3rd level), and of course, one parnet category above all of them.

I want to make a special single.php page for all of the posts, but the

<?php if(in_category($id)) { include 'special-single-page.php'; } ?>

only works for posts directly under that category and not for posts that are in sub categories of sub categories.

Is there a way to include a file for posts that are under several sub categories of the parent category?