My nine year old nephew hasn't lost any of his baby teeth but his permanent teeth have started growing behind them what can we do about this?

Ortho Eval: Schedule a consultation at an orthodontist. They should help guide you. Your nephew may need some primary teeth 'assisted' out by a dentist.

Visit dentist: If he has lost no baby teeth what so ever at age 9 and the adult teeth are erupting you should see a dentist. From what your describing it seems like he might need to have some teeth extracted.

See Dentist: To have the offending baby teeth extracted. Usually i tell my patients that if the permanent tooth pokes up before the baby tooth comes out, give two weeks for the child to get the baby tooth out on their own. If they can not then we extract the baby tooth. If there is enough room the permanent tooth will often move in to proper position on its own after a few weeks.