Rosina Blok was married previously married to Simon Hakker. In 1916 their daughter Kaatje Hakker was born. Kaatje Hakker died in 1917 shortly after her father had died. Addition of a visitor of the website
In addition, a Jokos file (number 21429) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.