Aaron Jacob de Groot and Sara Hakker had a son Jacob Aäron.
Haags Gemeentearchief, geboorteakte Jacob Aäron de Groot
Aaron Jacob (Arie) de Groot and Sara (Saartje) Hakker are mentioned frequently in the songbook for the marriage of their son Jacob Aäron to Anna Koekoek. Their daughters Roosje, Fijtje and Grietje are mentioned as well.
Collection Jewish Historical Museum
In addition, a Jokos file (number 005428) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.The Jokos file reveals that a claim was lodged for compensation for valuables surrendered to the Lippmann-Rosenthal looting bank (L-claim, number 4411 / 10994).