Sara Piller was a daughter of Duifje Boas.
Stadsarchief Amsterdam, archiefkaart Duifje Boas
This person is commemorated on a memorial in Vierhouten. More information on this memorial can be found (in Dutch) on the website of the Nationaal Comité 4 en 5 mei.
In addition, a Jokos file (number 10023) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.