Kaatje van Leeuwen was a daughter of Alexander van Leeuwen and Sara van Os and married 26 Augustus 1907 in Naaldwijk to Maurits Baks, a son of Abraham Jozef Baks and Saarte Frank. She had two children with him, Sara and Leentje. They were both killed in the Shoah.
After Kaatje and her husband were brougth into Camp Westerbork on 9 May 1943, the were deported on 11 may to Sobibor and killed immediately upon arrival there on 14 may 1943.
According Kaatje's registration card of the Jewish Council, she was "an inspector of the ecclesiastical bath since 1922 (mikwah)"
City Archive of Rotterdam, family registration card of Kaatje van Leeuwen (and Maurits Baks); website www.wiewaswie.nl; Archive of the Jewish Council, card of Kaatje van Leeuwen and an addition of a visitor of the website.