Although these kids are spectacular (how can one mark pictures with kids?!), I much prefer your older shot with the new born and only the hand holding him.
Perhaps I'm wrong attributing this to dirt_diver but I'm sure that he got a picture with a baby sitting just like this one
I actually think the girl is a bit distracting and takes away from the "artistic" nature of the shot- that being said, its got a warmer mood from the inclusion.