Izaak Theeboom was a son of Philip Theeboom and Catharina Voorzanger. He married Rebecca Lijmer in Amsterdam on 23 January 1929, a daughter of Wolf Lijmer and Rosette Swaap. The couple had three children together: Philip, Rosette andf Wolf. With their mother Rebecca they have been killed all on 27 November 1942 in Auschwitz. Izaak Theeboom was killed "somewhere" in Mid-Europe on 31 March 1944.
Izaak self was born into a family with eight children, of whom two of his sisters have survived the Holocaust. However, his sisters Lea, Anna, Debora and Rachel as well his brother Aron have been killed during the Shoah.
City Archive of Amsterdam, archive cards of Philip Theeboom, Izaak Theeboom and website www.wiewaswie.nl