Agathe von Trapp, a member of Austria's iconic singing von Trapp family, died on December 28, 2010 at the age of 97. The "Sound of Music" character Liesl, played by Charmian Carr in the film, was based on her. Pictured above, The Von Trapp sisters Maria (left) and Rosmarie (right) help celebrate Agathe's (Center) 85th birthday, March 12th with a surprise birthday cake at opening night festivities in the Martin Beck theatre for the Broadway revival of "Sound of Music". (UPI/Ezio Petersen)