In what year did Sigismund Casimir's mother die?
Cecilia Renata of Austria Archduchess Cecilia Renata of Austria (German: "Cäcilia Renata"; Polish: "Cecylia Renata"; 16 July 1611 – 24 March 1644) was Queen of Poland as consort to the Polish-Lithuanian Commonwealth's King Władysław IV Vasa.
Teofila Zofia Sobieska Teofila Zofia Sobieska, née Daniłowicz (Polish: "Daniłowiczówna") (1607 – 27 November 1661) was a Polish noblewoman ("szlachcianka"), mother of Jan III Sobieski, King of Poland.