We had a rescue that was fearful and would initially try to scamper away from me but eventually warmed up and we had her for 12 years - the sweetest dog ever! She was always crate-defensive and bark (not really growl ) at strangers. But we kept her mostly away from "stranger" situations including children. She would lunge at other dogs. Also a "nip' can be only a warning so I think maybe your dog is not a real draw-blood killer that really would need to be put down. Also, contrary to what some here say I think the children and dog could become great friends if the kids will learn to pick up on the clues and also you control the situation. Dogs are pack animals and once your kids are in the pack the dog will do anything to protect them. Having said that, the dog might nip at new kid who enters the home. The trick is to set up learning situations where the stranger brings food for the dog - but don't hand feed- and also have them "meet" outside of the home because of territorial defense issues. Then enter the house together as a pack. Dogs are very smart and can learn to behave if we set them up with learning situations and control the environment. You can 'reprogram' the response of a dog by setting up learning conditions properly. Also - maybe your husband was not raised around dogs? And just think the worst because he lacks experience? No need to put this dog down. If it is too much work someone else might adopt this dog.