Take him to a doctor and see if he has a medicla problem with his bladder/kidneys. If the docotr says nothigns wrong then take him into a therapist /physical therapist to help him learn to control his bladder /his muscles. Most likely this will clear up on it's own ,but it is better to get a medicla opinion first. And since i am not a doctor see a doctor instead of letting the kid think it's all his fault. Just my opinion.