Hartog Walvis was a son of Zacharias Walvis and Fijtje Posener. He married in Zaandam on 26 November 1913 to Jeanette Pront, from whom he was divorced there on 13 November 1918. Hartog and Jeanette had a daughter in 1914: Sophia.
On 9 August 1922 Hartog married again in Amsterdam to Elisabeth Maria Duijf, who passed away there on 3 November 1932. Hartog and Elisabeth had three children: Heintje, …