The Zeckendorf family firstly lived at the Schoonebeekstraat in Antwerpen. They later moved to the Lange Lausannestraat. A second daughter of Samuel Zeckendorf and Maria Beerenborg, presumably tried to flee to Vichy France. She didn't survive the war.
Addition of a visitor of the website
In addition, a Jokos file (number 004114) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.