Actress Heather Menzies-Urich, who starred in 'The Sound of Music,' has died. Menzies-Urich played one of the Von Trapp children in the 1965 film alongside Julie Andrews and Christopher Plummer. Her son told 'Variety' that she passed away on Christmas Eve in Canada after a battle with brain cancer. Menzies-Urich played Louisa Von Trapp, the third-oldest of the seven children in the Rodgers and Hammerstein musical. InsideEdition.com's Leigh Scheps (http://twitter.com/LeighTVReporter) has more.