Maria Agatha Franziska Gobertina 'Mitzi' von Trapp was the second-oldest daughter of Georg von Trapp and his first wife, Agathe Whitehead von Trapp. She was a member of the Trapp Family Singers, whose lives inspired the musical and film The Sound of Music. She was portrayed by Heather Menzies as the character "Louisa". She died at age 99, and was the last surviving sibling portrayed in the film.