Jacob Davidson was a son of Abraham Davidson and Elisabeth van Brink. He had four siblings, who all were killed during the Holocaust: Levie, Louisa, Elske and Bernard.
City Archive of Amsterdam, archive card of Abraham Davidson
Before the war Jacob Davidson already lived in France were he joined the France Foreign Legion. Probably he was send from France to Dachau where he died on 30 January 1945.
Source: Informatiebureau Rode Kruis – Den Haag