Hartog de Groot was married to Roza van Velzen. On 21 August 1943 their lifeless child was born in Westerbork transit camp and was cremated on 23 August 1943. The urn with the ashes was placed on the Jewish cemetry in Diemen on field U, row 11, grave nr. 21.
Register van joden die in het kamp Westerbork zijn gecremeerd, 1943-1944; archief van de gemeente Westerbork, opgenomen in het archief van de gemeente Midden-Drenthe te Beilen, inv. n 3789
In addition, a Jokos file (number 32052) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.