She wrote two books about her experiences, titled Forever Liesl and Letter to Liesl.
Ms Carr's spokesman Harlan Boll said she died of complications from a rare form of dementia in Los Angeles. Wow!!!
After Carr left the movie business, she started a design company called Charmian Carr Design.
She is survived by daughters Jennifer and Emily, four grandchildren Emma, Derek, William and Tucker, four siblings Sharon, Darlene, Michael and Brian
20th Century Fox paid tribute to the star, writing on Twitter: "The Sound of Music lost a beloved member of the family w/ the passing of Charmian Carr. She will be forever missed". She will really be missed.
May her gentle soul rest in perfect peace. She was loved and will deeply be missed.