when i saved files like..

/..../model/some/parent.php
/else/child.php

parent extends model
child extends parent

in some Controller I just want to use child class.
and I dont have to make a instance of parent (and.. it should be abstract)

so I want to include_once(parent.php) in some way..

but where should I put the codes in?

The code should be between after included model class and before include child class.

where is the right position? and how could I do?