My Quaker Parrot bites and is territorial and is mean to everyone except me (the owner) and my mother. From what I have seen, my friends would come to her cage, and my Quaker Parrot would start doing this frequent head bobbing that is very fast and she would lunge and attempt to bite them if they came any closer to her. And when they talk, my Quaker Parrot would make a louder version of her usual tweeting, as if she were yelling at them. This also happens if I'm holding her, or if my mother is, or if she's anywhere else, not depending on if we're holding her! She bites everyone else but me and my mom no matter what! One last thing, when her wings were not clipped and no one was in the same room with her, eventually, she would fly out of the room, and land on ANYONE'S head and start preening their hair, not making any attacks! This has been going on ever since she got comfy living in our home when we first got her (about almost 3 years). Help would be VERY appreciated!
P.S. When we first got her, it was pretty much only me and my mom that played with her, the rest of my family was really busy doing other stuff.