Why do parrots scream?
You have to remember that parrots have about the emotional maturity of a five year old. If their environment is stressful (i.e., cats stalk them or people rattle their cages) then they will start to scream. Parrots crave attention, and if they discover that screaming makes you run in and yell at them to stop, they will enjoy the attention and do it more. Spend a lot of quiet time with your bird, watch TV with them or do your homework with them haning out with you, I guarentee the screaming will be reduced.