My family had a Mitred Conure. At the time I was around 12 years old and while he seemed to get along fine with the rest of the family, he tended to be quite mean towards me. I never harassed him or hurt him, but if I ever got near him he decided to bite me.
I remember on one occasion while my dad was holding him during a molt, he was working on his pinfeathers, when he got upset, hoped across the couch, jumped on me and bit me. Did he decide that I was on the bottom of the "pecking order" and that if he had any frustrations he could take them out on me? He didn't seem to try to pull any of that on my parents.