Does she need to change her behavior? - 1

My 12 year old niece is acting very mature. She is a very nice girl she plays many sports and gets straight A's. But she is acting like a 16 year old. She wear high end makeup only wears brand name clothes she has a certain group of friends and a boyfriend. She wears high heels and dresses on certain occasions. She also cares very much about her looks she has her room re done every year. She has a brand new iPhone 5c an iPod and an iPad, TV in her room also. Does she need to change her behavior?

As long as she doesn't start acting rude or being really disrespectful its fine.

I think she does because if she continues like this. It won't be pretty one thing can lead too the other