LOS ANGELES -- Actress Heather Menzies-Urich, who played one of the singing von Trapp children in the 1965 hit film, "The Sound of Music," has died, The Associated Press reports. She was 68.

"Heather was part of 'the family.' There is really no other way to describe the members of the cast of the movie of 'The Sound of Music,'" Ted Chapin, president and chief creative officer of the Rodgers and Hammerstein Organization, said in a statement.

Her son, actor Ryan Urich, told Variety that his mother died late Sunday in Frankford, Ontario, Canada. She had been diagnosed with brain cancer.

"She was an actress, a ballerina and loved living her life to the fullest," Urich said.

The film's official Twitter account paid respect to the late actress on Monday.

Menzies-Urich played Louisa von Trapp, the third-oldest of the seven von Trapp children, in the film adaptation of the Rodgers and Hammerstein musical that starred Julie Andrews and Christopher Plummer.

"The Sound of Music" captured five Academy Awards, including best picture.

A Toronto native, Menzies-Urich's other film credits include "Hawaii" and "Piranha." On television, she appeared as a fugitive in "Logan's Run" and had guest spots on "Dragnet," ''Bonanza," ''Marcus Welby, M.D." and other series.

According to the BBC, Menzies-Urich posed nude for Playboy magazine at the age of 23 under the headline The Tender Trapp. Her decision to pose for the magazine horrified her parents.

She married the actor Robert Urich, who died in 2002. After his death, Menzies-Urich established the Robert Urich Foundation to raise funds for cancer research.

Variety reports that Menzies-Urich is survived by Ryan and two other children, several grandchildren and a great-grandchild.