Looking for a book written in the 60's or 70's - Father Earth may be on the tag

[Rick Harris]

I'm looking for a book written in the 60's or 70's. Young man lives with his mother either on a large space station circling the earth (or perhaps on the moon) and his father lives on earth. Father and mother had some falling out... Son has to go back to earth for a resupply mission (uses a shuttle so I'm thinking this wasn't written earlier than the 60's). Finds father and believes that the father is doing something important (trying to "heal" a post war torn earth and help the folks left behind).

I think the book's tag line might have the phrase "father earth, mother sky" or something along those lines....

I read this as a boy in the 70's and hoped to find a copy of it somewhere...

thank you in advance for your clues.....