[Ellie May]

You should not have to use a water bottle several times everyday. A few times and he should get the message (you always use it with a certain word - like NO). Then later you should just be able to use the word.

But this is a biting issue, so instead of trying to think of a way to punish him, you should seek the expertise of somebody trained in the field to work with your family immediately. It will only get worse if not dealt with.

Don't hit under any circumstances and make very sure your kids aren't playing too rough with him. It will only makes his problems worse.