[Ellie May]

I'm confused why this 9 month old would be so aggressive if you got him right from a breeder. Was he a rescue? Are you sure your kids or anybody else have always been gentle with him?

Petsmart is more for basic obedience and not for behavioral issues. A behaviorist is needed. I know you are stressed over this. I'd say if you don't have the time or money to make this work, then it is best to surrender him to a Yorkie rescue. I wonder if the kids are just too much for him right now. Either he or they are going to get hurt one of these days if this isn't immediately and properly dealt with. I know money was an issue last time. If you have come up with it and can spend the time training, then maybe the American College of Veterinary Behaviorists site would be a good place to start.