Jacob Joseph Sternfeld and Rosette Worms married in 1907 in Amsterdam. They had five children. Besides the here mentioned children they had a daughter Frouke and another child that did not live at home anymore. One child survived the war.
Stadsarchief Amsterdam, archiefkaart Jacob Joseph Sternfeld
In addition, a Jokos file (number 51295) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.