How to use custom fields with a child theme

Hi all,

I have been tinkering with WordPress and was wondering if you guys could point me in the right direction. I am managing a site where admins post content created by other people, requiring custom fields for managing guest-authors.

I have two custom fields I wish to display on my site. One is feed-author, which determines the guest author(s) to be displayed in the feed; the other is read-author, which determines the guest author(s) to be displayed when reader is in single post or page view. The reason I have two is that sometimes I like different information to be displayed.

I use a child-theme for all my customizations, and was wondering how best to implement this through a child-theme? I would like to display the feed-author under the title in my feed; and display the read-author under the title in single post view. All manuals online state that I have to edit my main functions.php file but I’d rather do that through a child-theme. Is it possible?