Nothing I can do I think...staying for another week with the ILs, DN is a huge 19mo, DS a small 25mo, DN is bigger. He is a bit of a disturbed child I think, not much consistency of care, plus am abroad and parenting styles are v different. Anyway, he and DS have lots of fun, but punctuated by regular bites. Poor DS keeps coming to me and saying 'no adam bite' with a sad face and poor DN keeps getting slapped but it's doing fuck all. I know children this age bite but DS has started slapping DN when he gets near him which is behaviour I don't really want him learning. Short of watch them like hawks (which doesn't even stop it) what can I do?