Jacques de Vries, a musician, was married to Rozette Kropveld. They had no children. The couple lived in the 2nd Oosterparkstraat 77 in Amsterdam, the same address as his parents-in-law, Samuel Kropveld and Goetje Kropveld-van Cleef.
NIOD, Records Stichting Sieraden-Comité, box 7HF, file 101
In addition, Jokos files (numbers 15657, 30946, 51654) on this family or other family members are at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.