The Sound Of Music star Charmian Carr has died at the age of 73.

The actress’s spokesman said she died on Saturday in Los Angeles, of complications from a rare form of dementia.

Charmian Carr with the stars of the Sound Of Music musical (Yui Mok / PA)

Carr was best known for portraying Liesl von Trapp in Rodgers and Hammerstein’s 1965 film, in which she performed the song Sixteen Going On Seventeen.

She was a college student when she auditioned for the film, which also starred Julie Andrews and Christopher Plummer.

Carr later wrote a pair of books about her experiences, Forever Liesl and Letters To Liesl.

The actress went on to star with Anthony Perkins in the Stephen Sondheim television musical Evening Primrose.

Kym Karath, who played Gretl, the youngest of the von Trapp children, was among those leading the tributes on Twitter.

It is with infinite sadness that I share the tragic news that the precious & exquisite Charmian Carr , beautiful Liesl , has passed away .

— Kym Karath (@KymKarath) September 18, 2016

One of Charmian's and many happy times together . She has been like a sister throughout my life . Excruciating .

— Kym Karath (@KymKarath) September 18, 2016

The Sound of Music lost a beloved member of the family w/ the passing of Charmian Carr. She will be forever missed.

— 20th Century Fox (@20thcenturyfox) September 18, 2016

So very saddened to hear of the death of Charmian Carr. She leaves behind one of the most memorable performances in movie history.

— Seth MacFarlane (@SethMacFarlane) September 18, 2016