Abraham Salomon Koster had three brothers and three sisters. Two brothers died before the war. 449946, 449950, 448129 and 517898 all perished in Auschwitz.
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Abraham Salomon Koster was married to Rosalia de Wolf. With her he had four children among them Levie, also known as John, and Maurits Koster who didn't survive the war. Rosalia de Wolf died in 1919. Abra…