I adopted 2 children one from orphanage in Riften and a girl Solie from one of the other cities. I can gives gifts to my son but when I try to give a gift to Solie the list of gifts come up but they're not highlighted and I'm unable to give her anything and she says "Ahh stop teasing me,pa". Any idea how it fix this if possible.? I'm on 360

Did you get "girl" stuff for Sofie?? Try getting her an iron dagger, or a dress, or a doll.

yes, I have a doll in my inventory

In the unmodded game, can you adopt more than two kids? I can't remember.

I've only adopted 2

Yes, in the UNmodded game you may adopt up to 2 children.

Try clearing the cache, and then re-loading. Also, try moving to a house in one of the cities, and then back again. I do not know what else, except to try an earlier save. She is the best one of the girls, in my opinion.

http://www.uesp.net/wiki/Skyrim:Sofie

Here is a list of the gifts one can give.

http://www.uesp.net/wiki/Skyrim:Adoption

If you mean Sofie...she has an inventory full of flower baskets,she is carrying too much weight and can't be given gifts...get the speech perk and buy all of her inventory before adopting her.

This. Sometimes, I do not know why, Sofie's inventory gets bogged down with flower baskets. UESPWiki has a little bit on it http://www.uesp.net/wiki/Skyrim_talk:Sofie.