I have a seventh month old lab/collie mix I got from a rescue. I understand puppies need to chew but she is overly agressive. I will pet her and she will snap at you and jump up and try to bite. I have tried walking away and ignoring her, replacing her biting with toy, putting her in her crate, spraying her with water, and ultimately, having to physically restrain her which I am very unhappy about. Mouthing i get, but not sure what to do with this behavior. She is smart and sweet at times, but i have two very young kids so i worry.