Michel Kosman was a son of Barend Kosman and Leentje Pachter. He married Schoontje Harpman on 30 April 1924 in Amsterdam, a daughter of Philippus Harpman and Sara van Gelderen. Michel was in the flower trading, just like his father. Afther his marriage Michel and Schoontje resided in Antwerp, where his son Bernard in 1925 and daughter Sara in 1927 was born. His son Philippus was born in 1934 in Amsterdam. His wife Schoontje and the children Sara and Philippus were killed in Sobibor on 26 March 1943; his son Bernard lost his life in concentration camp Buchenwald on 10 February 1945. Self Michel Kosman has been killed, somewhere in Europe on 31 March 1944 during the Shoah.

Michel was born into a family with six children. His siblings Betsie and Gerhard have survived the Holocaust. However, not his brother Maurits and his sisters Evalina and Duifje: they too have been killed in the Shoah.

City Archive of Amsterdam, family registration card of Barend Kosman; Municipal Archive of Den Haag, family registration card of Michel Kosman; website www.wiewaswie.nl and the Dossier of Foreigners of the City of Antwerp, dossier nr. 177089 (images 84-94).