Turns out Wolfgang Amadeus Mozart had a sister who was an outstanding and well-known talent at the harpsichord and, from the sparse evidence, an able composer as well. Sylvia Milo found this historical omission an unforgivable lapse and decided to let audiences know all about Maria Anna "Nannerl" Mozart. She wrote "The Other Mozart," which stars herself and Jody Christopherson (as well as other actors in rep).