I'm sorry you're having such trouble with your dog. Unfortunately, there are many factors involved with canine aggression. At what age did you get her? When does she show you her teeth and what is the situation at hand when it happens? What mix of breeds is she? Why does she sleep under your bed? Is she ever affectionate with you and if so, under what circumstances? I can try to answer your concerns but as I said, it is difficult without more details. Even afterword, I can't guarantee a solid answer. However, I will try my best to help you.
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