Jacob Loonstein was a son of Emanuel Jacob Loonstein and Saartje Boutelje. He married in Amsterdam on 7 September 1892 to Naatje Speijer, daughter of Jacob Leendert Speijer and Marianna Emanuel Schrijver. Jacob and Naatje had 9 children: Emanuel, Marianne, Maurits Jacob, Herman, Isidore, Simon, Sara, Bertha and Leendert, who died in childhood as a baby.
Naatje Speijer passed away on 2 January 1919 and was buried at Muiderberg. Jacob Loonstein remarried in Zaandam on 27 May 1920 to Saartje de Haan from Leeuwarden, daughter of Philip Simon de Haan and Racheltje Polak.
City Archive of Amsterdam, archive card of Jacob Loonstein and website www.wiewaswie.nl.
Biography