JackJack Attack is a 2005 computer animated short film produced by Pixar based on their film The Incredibles, and directed by Brad Bird.
This short film shows Rick Dicker, a government agent assigned to aid supers in maintaining their anonymity, interrogating Kari about what happened when she was babysitting.Kari calls Mrs. Parr to assure her that she can take care of JackJack, but is cut off by the plane being fired upon. Thinking nothing is wrong, Kari asks JackJack if he is ready for some neurological stimulation. She puts on Mozarts Piano Sonata No.for him, which has the result of JackJack having an epiphany about his latent superpowers. ........
Source: Wikipedia