If it makes her feel better maybe she should get it done (but I don't think it's necessary). She should do some research on the risks of this procedure. If she still wants to go through with it she should try to find an experienced plastic surgeon and ask to see before and after photos of previous patients. Maybe instead of surgery she can try some new butt exercises to help lift the butt area. Or she could just accept herself the way she is and the fact that nobody is perfect; looks don't mean everything.