Hi I have a 3 year old parson terrier bitch. She is sweet natured but shows aggression including attacking my brothers 2 terrier bitches. They are about the same age. I had mine for 2 years then my brother introduced his two. I think it might be the alpha female thing. She has already ripped one of the terrier ears and first no reason attacks them. She has never shown aggression to other dogs. Just these two. They are at my house during the day. Any ideas please. She is a rescue dog I've had since a puppy. The others two are also rescue dogs.