Mendes Davidson was a son of Jakob Davidson and Jantje de Jong. He married Rebecca van Kolm in Amsterdam on 26 May 1921, a daughter of Coenraad van Kolm and Sara van der Poorten.
The family he was born in, counted seven children: besides a sister who probably has deceased before the war and a brother who has survived the war, his other siblings Simon, Sara, David Jakob, Iseroos and he himself were…