Education
HU University of Applied Sciences Utrecht. Windesheim University of Applied Sciences.
HU University of Applied Sciences Utrecht. Windesheim University of Applied Sciences.
From 6 February 2014 Siderius temporarily replaced Renske Leijten who went on maternity leave. When Paulus Jansen resigned in April 2014, Siderius became his permanent replacement on 14 May 2014. Henri Swinkels then became the temporary replacement for Leijten.
Siderius studied management, economy and law at HU University of Applied Sciences Utrecht between 2001 and 2001, she continued studying at Windesheim University of Applied Sciences on the topic of personnel and work between 2001 and 2005.
She has been fraction leader of the Socialist Party in the municipal council of Zwolle since 2007. During the 2012 general election Siderius was number 18 on the Socialist Party list and received over 3000 votes.
The Socialist Party conquered 15 seats and as a consequence Siderius was not elected.
She was a member of the House of Representatives of the Netherlands for the Socialist Party between 3 September 2013 and 26 November 2013, temporarily replacing Sadet Karabulut, who went on maternity leave. Siderius had been a staff employee for the Socialist Party fraction in the House of Representatives before she became a temporary member of the House herself.