Izak Bonavang was a son of Nathan Bonavang and Roosje Velleman. He married 10 March 1926 in Rotterdam to Saartje Velleman, a daughter of Alexander (Hartog) Velleman and Kaatje Koster. The couple had one daughter: Roza.
City Archive of Rotterdam, index marriages, family registration card of Izak Bonavang and an addition of a visitor of the website