Bertha Wolfsbergen was a daughter of Leonard Wolfsbergen and Mathilde Sohn. She married the non-Jewish Hendrik Krijn on 24 December 1914 in Rotterdam, a son of Hendrik Krijn and Dina Vlaander. The couple had two children who have survived the war. Bertha's husband passed away in Rotterdam on 25 August 1941 but Bertha self has been killed on 15 October 1942 in Auschwitz.
City Archive of Rotterdam, family registration cards of Hendrik Krijn and Leonard Wolfsbergen and the website www.wiewaswie.nl.