Be careful not to confuse Maria
Agusta Von Trappe (who was played by Julie Andrews in the movie) with Maria
Franziska Von Trapp who was the second eldest daughter and one of the children.
The confusion comes from the movie where Maria Franziska (one of the children) is called Louisa! Reportedly, this was done to avoid confusion of having two characters named Maria in the movie.
Thus, it was Maria Franziska (aka Louisa, last survivor of the original Von Trappe children) who recently passed away.
Her stepmother, Maria Agusta (played by Julie Andrews and recently by Carrie Underwood) passed away in 1987.
This is how most of us remember Maria Franziska, aka Louisa, as played by Heather Menzies in the movie (third from left):
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