Child theme edition

Hi, anyone could help with the following questions? Thanks a million in advance.

I’ve engage a programmer to help me with a creation of a child theme, he got the following question, would appreciate any help.

1) Is it possible to include modification I did on class files to the child theme?
How to include modifications I did on class_white_label_themes.php (\framework\class)
to the child theme?
Should I include it under _functions.php ? I tried that but did not succeed. Can you please help me with some insight in to this.

I had modified following class files as well.
class_admin.php, class_gateways.php,

2) Is it possible to include changes I did on Admin to the child theme.
I modified following files on the Admin (\framework\admin).
_0.php to -11.php