Custom post child defaults to index.php

Hi all,

I have created a custom post type and set it as hierarchical=>true and for it to feature page-attributes so that I can specify child and parents.

The custom post type is called services, I have a single-services.php template set up which is being used correctly for the parent custom posts however if I try and view a child custom post it tries to use the index.php file.

How can I make the child custom posts use the single-services.php template too?

Thanks,

Phil