Boo is the goofiest, sweetest, most lovable lap dog, but has become increasingly aggressive with other dogs. He has recently attacked other dogs including my other dog, and is unpredictable now with other dogs. If he starts to attack, he has to be pulled off the other dog, he just won't stop. Barking is his trigger. He is great with cats, chickens horses and humans, but I am fearful for other dogs, as he has tried to kill them. He is going to be euthanized tomorrow.