Apparently, Isaboo, a pit bull, has had five incidents of violence wiht other dogs. Here's what Radar has to say about the latest incident:
The latest incident with her dog occurred in early February in New York City when Isaboo lashed out and ripped off another dog’s ear! According to an exclusive report in the National Enquirer, the dogs and their handlers were walking by each other in Greenwich Village when the attack occurred. “As the other dog walked by, Isaboo lashed out so quickly and ripped the other dog’s ear off before its handler could pull it away.”
The other dog is apparently fine and it's ear has been fixed. Check out the full story here. If this story is true, then I am really sorry for Rachael. She has said many times how much Isaboo means to her, so this would be heartbreaking.