My LO got his top two teeth a little over a month ago and now that they are in all the way, he's all of the sudden biting my shoulder or arm constantly. Basically every time I hold him he bites. I've tried saying "No!" forcefully, tried saying "Please don't hurt Mommy," but he just laughs. Besides wanting it to stop for my own pain, I'm nervous he will bite another baby at day care. Any tips for reasoning with a 10 month old?!?