Elisabeth de Leeuw was the widow of Isaäc E. Cassier, who had died in Leiden on 7 January 1930. They had three children: Emanuel, Hendrika and David. In 1898 (before David was born) the family moved to Alphen, where they lived at 31 Visserstraat. Emanuel and Hendrika never married and remained at the Visserstraat residence until 30 September 1942, they day of the massive raid in Alphen. Jews were fetched from their homes by Nazi troops and Dutch police officers and sent to Westerbork via Amsterdam. Emanuel Cassier was a furniture maker by trade and was active in the Jewish community in Alphen. His offices included serving as secretary to the board of the synagogue. The records reflect that he surrendered a four-lamp Albibiani radio to the Alphen police on 21 April 1941. Hendrika Cassier had no occupation.
L. de Brouwer, De Joodse Gemeente Alphen aan den Rijn, 1792-1964 (Haarlem 2002) 33-35
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