Jansje and Branca Koren were daughters of Israël Koren and Betje Polak. Jansje was born on 7 January 1895 and Branca on 13 June 1898, both in Amsterdam. They had a brother Isaac, who was born in 1893, but after his divorce he left for Kaapstad in South Africa in 1929. Their mother Betje Polak had died already in 1905 and their father remarried then Rosette Mozes and after her passing, again to Sel…