Joseph de Leeuw was a son of David Jacob de Leeuw and Rosette Baroche Hamburger. He had four other brothers: Jacob David, Emanuel, Abraham and Alexander Louis.
Joseph married on 20 September 1905 in Arnhem to Betje Fortuin, daughter of Maurits Fortuin and Mietje Zwartz, and together they had two children: David Jacob, who survived the Holocaust and Mietje Dina Sophia.
City Archive of Amsterdam, a…