Ontama!

although the main characters have different reasons of having problems with their fathers and Ontama have a comedic tone while Clannad AS doesn't, in both with an intermediate person, they overcome through their problems, also in both there's a supernatural element involved. 

They are heart touching stories about the relationship between father and daughter. 

Both feature little kids as main characters. Both deal with love relationships featuring adults. Both have a trio of children that plot to help certain characters fall in love. Also, both deal with the importance of family and human vs human relationships. Overall they're both pretty good G rated anime, for anyone that just wants to relax and watch something nice and entertaining. 

Both are about the importance of bonds. Both deal with the main protagonist meeting someone someone from her family that cames from the future. Both are cute animes to a younger audience.