Thanks everyone ! I'll be sure to show my mom this. I'll try to convince her that its the owner that is responsible for the nipping. I know why BooBoo nips: my aunt spoils him to death. Everytime he nips someone she just grabs him, puts him on her lap and pets him. Basically encouraging an unstable mind.

I'll also tell her about the 'oversized' chihuahua. Maybe that one will encourage her.