Max Louis and is brother Eduard (usually known as Eddy) were sons of Levie Crost and Sophia Zegerius. Together with their parents they were deported from Westerbork to Auschwitz on 14 September 1942. Their father had to leave the train during a stop in Kozel and ws employed in the forced labor camp of Blechhammer.
Their mother, Sophia Zegerius was killed immediately after arrival in Auschwitz on 17 September 1942. Max Louis and Eduard arrived the same time in Auschwitz however their exact dates of death are not known. Therefore, after the war, the Dutch authorities have established their dates of death as in Auschwitz on 30 September 1942.
Sources among others: the file cabinet of the Jewish Council, registration cards of Max Louis and Eduard Crost, website wiewaswie.nl and the City Archive of Amsterdam.