I don't think it's true that yorkies do not like children. That's definitely a generalization. My yorkie looooves children and has never nipped. In fact we were just with a friend of ours who had her little 8 month old baby, and she was petting him and loving him, and he was sooo excited. He loves all our nephews and niece. Miko was checking on her when she was taking her naps to make sure she was okay
And they even let him wake her up. They put him up on the bed where she was napping, and he walked over to her and watched her sleep and layed down by her. Then, he got up and licked her nose
Sorry to get off topic, I just wanted to let you all know that not all yorkies don't like kids.
I'm sorry that you're having to go through this. Biting is a serious problem, and maybe you could get a trainer for him. I think that with proper training, he can learn to not behave that way. Keep us posted, and I will be praying for your furbaby!!! Again, this situation just stinks.
Could it be that he's in pain or something is wrong with him, and he's just taking it out on her? I don't know if this is a possibility, but maybe?