Ido (Isidore) Monnikendam (7/1/1925 - 5/28/1943 Sobibor)
Jaap (Jacob) Monnikendam (7/29/1927 - 5/21/1943 Sobibor)
Bettie (9/14/1933 - 5/28/1943 Sobibor)
Hanneke (7/14/1939 - 5/28/1943 Sobibor)
Jacob attended the Jewish Lyceum (academic high school) in Amsterdam in 1941-43 (see Dienke Hondius, Absent, p. 273).
Ido may have attended the Gymnasium (high school) in Hilversum where they lived until April 1942 when all Jews from the provinces had to relocate to Amsterdam. The parents, Saar and Bram, with the two little girls moved in with Saar's brother's family, Gerrit and Ka Ossedrijver-Kleerekoper at Transvaalstraat 36huis, Amsterdam. We do not know the family that took in the two sons.