Joseph was a doctor, located at: Nieuwe Prinsengracht 45 - Stadsherstel Amsterdam until 1905; in 1901 co-founder and chairman of "de Nieuw-Malthusiaansche Vereeniging" (split from the Nieuw-Malthusiaansche Bond). On 15-6-1909 he married Mathilda Paulina Hollander in Rotterdam. They have 1 son who emigrated to Brazil in 1951.
Source: StadsherstelAmsterdam