No, it does not seem to me to be "typical" of a 3 1/2 y/o. At that age, she should know how to share/take turns, how to play alongside kids somewhat co-operatively, and in general how to get along with people. That doesn't mean that she is not capable or that something is "wrong", it means that she hasn't been taught. In addition to being an only child, I would guess that she does not get a lot of social interaction with other kids unless she is at your place. I guess what I mean is that it is "typical" of a child that has not been properly socialized. Mommy and Daddy clearly still think of her as their little baby. Unfortunately, I don't have any more advice than what has been mentioned already. If you can, I would find a way to talk to mom or dad. It may not make a difference, but at least you can say you tried!