"Daddy’s Roommate"
In this picture book for ages 2-5, Frank and Daddy are seen pursuing their daily routine; and on weekends the entire family goes on various outings.
It's a useful and straightforward view of an alternative family, and the format - single lines of copy beneath full-page illustrations - are great for kids and adults.
Daddy's Roommate was one of the first children's books to portray gay life in a positive way; the gay couple do the same things heterosexual couples do: Take care of the house, argue, and spend time with their kid.