Please tell us, what happened before the dog attacked? We might be able to help you. The dog nipping you, and the dog attacking Chad could be two totally seperate issues. I can 95% guarantee that the dog used biting to get away from something. I call it a trigger...Chad did something that mr. biggles has experienced discomfort from before, and used his teeth.

Did you see the attack?

Has the dog seen the vet? Didn't you say somewhere that Mr. Biggles might be either hard of hearing or partially blind? I can't remember...