Samuël de Leeuw and Esther de Lange married in 1915 in Amsterdam. Besides the here mentioned children they had a daughter Mina.
Stadsarchief Amsterdam, archiefkaart Samuël de Leeuw
In addition, a Jokos file (number 14862) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.