ok, listen...do you spank him? Alot of parents out there are saying 15 months to young...in fact you are probably screaming at me already right? My son who is now 7 was the same way, however I also dealt with biting, scratching and then he started banging his head on the walls and the floor! You get to a point when you feel there is nothing you can do? I know the feeling. I decided to show my son how it felt...I scratched him if he scratched me...I bit him if he bit me and I only had to do both of these things one time and he stopped doing these things right away...hey when your hands are tied, your hands are tied. The head banging stopped when he hit his head on his aunts concrete floor and hurt himself pretty bad...that was the end of that. Im not saying this "SPANKING THING" is the best idea...but it sounds like something I would do and you asked!!