I've read one story from a foreign yorkie forum. Yorkshire terrier was attacked by pitbull. the condition of the dog has been
very serious: his lung was bitten through and even vets (an owner took many possible advices)haven't given any guarantees.
The owner does all her best. I respect people like she soo much. Hopefully, her yorkie will be fine.
But there are another people in this story - owners of pitbull.
I hate people like them and feel sorry for its dog. I believe, there are NOT a bad dogs, they are bad OWNERS. When yorkie's owner called them and told what happened (she wants to return her vet bills), they said:" what do you want from me, my dog dosn't like small animals. Do you want me to put my dog down? Why do you spend so much money and ask me to pay all vet bill back to you when no guarantee? Let's
I will buy a new dog for you 
and you will leave me alone". When she asked him to control his dog, he said:" I cannot control him, he doesn't let me to do that, and you shouldn't have small fry"
Unbelievable
trash
she is going to sue them....