our older son, who is now 15 was and still the same way. It concerned us at first. He never socialize with any child when he was also two. We tried parks, leaving him with daycare, and we get word from daycare that he isolates himself from everyone and does his own thing. Yes, we were very concerned. Now at 15 years old. He is stil the same way. Every get together we have ever had, or attended, he with refused to go and just wanted to stay home and wait till we get home, or he goes, but ready to leave right away after a short time we arrived. If he chooses to go with us, he sits alone, does not say anything to anyone, or he wants to stay in our vehicle and wait till time to eat. We have get together at our house, everyone else socialize, he locks himself in his room and never seen till one of us calls him its time to eat. He fixes his plate then disappears. But, one thing, he makes great straight A grades, a well loved and liked by his football team and coaches, and his teachers. He never says much at all according to his teachers, but when he is asked to do somethig, he shows so much respect to his surrounding peers. If he tackles someone of the opposite team during football, he goes right back and reaches out to help his opponent back up on his feet. Still, he does not socialize. He is off on the side or sits alone during gatherings....LOL!...so we don't see now anything bad out of it. But one thing I noticed, he is very close to his Dad and they do a lot of father-son things together, going to the movies with his younger brothers too on the weekends, to the game store if he wants to go shopping for something but he just walks in the store, get what he wants and ready to go home, etc. We also have two more younger boys now at ages 14 and 12 and are totally opposite from the oldest one. Yet, they all make straight A's at school and continuing to persue with their football games. So his youngest brother loves to play with him, sometimes the 12 year old will try and get on his last nerve just to try and bring him out of his zone....LOL...You never know. My advise is just watch her, and don't force anything out of her. It may just be a temporary thing or it might be just something of her that slowly but surely changes or may not be at all. There's nothing wrong with it :)