My Sun Conure is super sweet when it comes to me and my sister but I noticed that whenever my mother approaches him, he grows all fluffy and enters some sort of " battle mode ". He will open his beak and keep moving his head up and down, as if he is nodding, with this crazy look in his eyes. And whenever my she tries to touch him, he lunges and bites her. I made her give him a treat once and he was okay with her for a while but after that his aggression returned. Is there any way to make him more friendly with her?