As far as the pee pad training goes, I have quite a ways to go w/that. But, Bella mouths everything. She constantly bites my hands.. I have picked up a few pointers that I've noticed a difference now after trying them. I took a facecloth & cut it up into thick 3" long strips & soaked them w/water. I freeze them and when she's biting a lot, I give her one to chew on..I think it does comfort her gums some. Also consistency is important, I say no or no bite when she puts her mouth on my hands..I say it kinda loud but def don't yell it. If she bites me after that, I put her in time out. That's in her crate left alone.. She still bites me but honestly I am noticing a difference finally. It was nonstop before & now I see her thinking about it. So good luck & he will understand soon enough that he can't use your hands as a chew toy!