Rosette is een dochter van Isaac Asscher en Marianne Sarlouis. Ze trouwde 25 april 1911 met Arie van Amerongen (A'dam, 24 juli 1874 - A'dam, 21 januari 1939).
Rosette died in hiding, in an aged home she had been placed in by helper Sytske Ketelaar, who was awarded Yad Vashem's Righteous Among the Nations award for helping Rosette and other Jews.