Media appendix
Duifje Fresco 02.01.1873/11.06.1911
I think you mean Duifje Fresco a sister of Betje Fresco. She married Benjamin Levie van der Sluis 22.08.1873/30.09.1927 Rotterdam. They had 9 children. Most of them died in Auschwitz fi their son Marcus Leendert van der Sluis.