Number 28 on this picture of the Joodsche HBS of 1937. She joined voluntary with the patients on the trains when they were taken away by the Germans. Betty de Haan did not survive. 12-2-1943 Auschwitz. Her mother was a daughter of Chief Rabbi Onderwijzer. The father of Betty was a brother of Jacob Israel de Haan. See link below and also for more in Google.
http://en.wikipedia.org/wiki/Jacob_Isra%C3%ABl_de_Haan