My son is 9 years old and just started wetting his bed this past month ... what can i do for him?

It is a concern when your son has started wetting the bed at his age. The first thing to do is to schedule a medical exam for him as this can be an indicator that he has an infection which needs to be treated. If it turns out not to be a medical issue, this could be due to stress. If there is something going on at home or at school that is causing him anxiety, this can contribute to bedwetting. He may just need you to listen to his problems and give him some reassurance. Figuring out the cause whether it's medical or psychological may just lead to drier nights in the future.