Marianna Hekster, a daughter of Zadok Simon Hekster and Rebekka Groen, married in Amsterdam on 6 July 1898 Emanuel Kool, a son of Israel Kool and Saartje Goudsmit. The couple had two children: Israel and Rebekka, who both with their families have been killed in the Shoah too.
City Archive of Amsterdam, archive card of Emanuel Kool and website www.wiewaswie.nl