Hi. I read your post and while my partner and I are working through surrogacy to become parents, we read a book titled, "Gay Dads" by David Strah. The book is a compilation of stories of families that came about by adoption, foster care, surrogacy, marriage (and then divorce) and yes, co-parenting (pg 77, "a fatherhood not by design"). I bought the book at Barnes and Noble and I think it could provide a bit of insight for you. Good luck.