Mozart The second woman in Mozart's life was his older sister Nannerl. The two started out as partners in music, but Nannerl's career got sidelined when young Wolfgang turned out to be a genius. Dezso Ranki and Zoltan Kocsis play the Presto from one of the kids' early duets, the Sonata in B-flat Major, K. 358. From his road trips Mozart sent back music for Nannerl to try, including a wacky Modulating Prelude and the Capriccio, K. 395. Ton Koopman is the harpsichordist.