she is the last of the original singers (although I believe several of the much younger children of the more famous Maria, the second wife, are still alive).
NYTimes obit here: She is survived by her half siblings and her adopted son...
Factoid: She served as a missionary in New Guinea, (where the stepmom Maria joined her for a few years).more HERE
In 1956 the Trapp Family Singers had toured Australia, New Zealand and the South Pacific... the von Trapps promised (the bishop) they would go to the islands and start lay missionary work...Stepdaughter Maria (b 1914) and children Rosemarie (b 1929) and Johannes (b 1939) had just arrived in PNG. Maria and Rosmarie taught "the little ones" and tended the sick in villages while, among other chores, Johannes built a church and two schoolhouses. He remained in PNG for four years, Rosmarie for five and Maria for a dedicated 30.