The singing star died in her home in Vermont on Tuesday, her half-brother Johannes von Trapp has confirmed.
"She was a lovely woman who was one of the few truly good people," he said. "There wasn't a mean or miserable bone in her body. I think everyone who knew her would agree with that."
Maria was one of the original seven members of the family band whose story inspired the 1959 Broadway hit and 1965 popular film The Sound of Music starring Julie Andrews. The movie won an Oscar for Best Picture.
Maria, who was portrayed as Louisa in the film and musical, was the third child and second-oldest daughter of Austrian naval captain Georg von Trapp and his first wife Agathe Whitehead von Trapp.
Georg's second wife, also Maria von Trapp, wrote a book in 1949 which became the basis for The Sound of Music. The story tells of an Austrian young woman, Maria, who leaves a convent to act as a governess and music teacher to the Von Trapp children. Maria and Georg fall in love and end up marrying, but the family have to flee Nazi-occupied Austria for the US.
Much like in the book, the late singing star and her family fled Austria in 1938 and ended up performing around the US. In 1942, the von Trapps settled in Vermont where they were singing on tour, and later opened a lodge in the town of Stowe, which they still operate.
Writing in a blog post on the lodge's website, Maria described how it was her ill health as a child that made her father hire a governess to teach the children from home.
"As a result of scarlet fever, I was too sickly to walk the three miles to school every day, and the doctor advised that I stay home," wrote Maria. "This condition brought Maria Augusta Kutschera to teach me first grade gymnasium, the equivalent of middle school.
"She came to us as my teacher and after three years became our second mother. On November 26, 1927 they were married and would have three children, Rosmarie, Eleonore and Johannes."