hhunterr - This is a good question. This young lady was born with a vocal instrument nearing perfection. Her vocal range is 3-4 octaves and her tone is mature beyond her years.
Additionally, she is wise enough to study correct vocal technique and learn how to care for her voice.
Jackie's brain has the ability to coordinate with her voice. She can imitate certain sounds. Upon the young singers attending the musical, Phantom of the Opera, she was able to duplicate the female voice in the film.
How? Why? If I knew the answer to that, I would be publishing books left and right. :)