Margaret "Gretl" Stonborough-Wittgenstein, of the prominent and wealthy Viennese Wittgenstein family, was a sister of the philosopher Ludwig Wittgenstein and the pianist Paul Wittgenstein. She was the subject of a famous 1905 portrait painted for her wedding by the artist Gustav Klimt, which was sold in 1960 by her son Thomas and may now be seen in the Neue Pinakothek gallery in Munich.