Jacob Frank was the second of the six children of Levie Frank and Henderina Cohen, born in the 1e Pijnakkerstraat 105a in Rotterdam on 15 June 1900. He was an office clerk by profession and on 11 November 1925 he got married in Rotterdam to Marianna Rebekka Florina de Leeuw, who was born on 31 January 1904 in Rotterdam as daughter of Salomon de Leeuw and Klara Brest. She was the sister of Betje de…