I call it Blue Parakeet aceo.
When I was little we had a green parakeet like this, his name was Chippers, and I swear he taught me to whistle. I was probably about 5 and was trying to learn to whistle. So I sat infront of Chippers cage, he whistled all the time, and I practiced and tried until I finally did whistle. So my parakeet taught me to whistle, and no one will convince me otherwise.
He also was a little escape artist. I remember coming home from church and finding him flying around the house. We had to put a twist tie on his cage door so he couldn't do that anymore. He loved my mom. We had a huge mirror hanging over the stiars, and he liked to sit on that. He also loved cheetos, ya, I know it probably wasn't good for him, but this was in the early 70's, who knew?