Israel Kleerekoper was a son of Gerrit Kleerekoper and Eva Betel. He married 19 December 1934 in Amsterdam to Lea van Praag, a daughter of Joschem van Praag and Betje Groenstad. the couple had one son.
His siblings, who also have been killed during the Holocaust were 488484, 527763 and 488481.
City Achive of Amsterdam, archive card of Israel Kleerekoper and Lea van Praag,