Max is a rescue and has been in our home for 2yrs. He is 3 yrs old. His previous owner was abusive and he was crated a lot. Last year, he was attacked by our neighbors dog and has several scars from this attack. He has only ever bitten when being put in his crate and since then we don't use his crate we use the bathroom and his behavior is better. He would bite when on a leash or confined. We just avoid these stressors. Yesterday out of no where he bite my 18 yr old niece in the lip. I don't know what to do with him.