As reported in The Telegraph:
Deutscher's father said she could name the notes on a piano by the age of two. She was given her first violin for her third birthday, and was playing Handel sonatas within a year.Reposted from 2012 (the embed above shows her performing at age 6) to add this incredible video:
Earlier this year, Deutscher composed a short opera called The Sweeper of Dreams, which narrowly missed out on making the final of a contest run by the English National Opera to unearth young, talented classical musicians.
Scott Pelley selects four notes, and the now-12-year-old young lady takes less than a minute to compose and play a piano sonata based on those notes.
Via Neatorama. Her Wikipedia page.