Question: Who was married to Sigismund III Vasa, and mother to Władysław IV Vasa?
Related documents: [0]  [DOC] Constance of Austria (German: "Konstanza" ; Polish: "Konstancja" ; 24 December 1588 – 10 July 1631) was queen of Poland as the second wife of King Sigismund III Vasa and the mother of King John II Casimir. [END] 
[1]  [DOC] John II Casimir (Polish: "Jan II Kazimierz Waza" ; German: "Johann II. Kasimir Wasa" ; Lithuanian: "Jonas Kazimieras Vaza" ; 22 March 1609 – 16 December 1672) was King of Poland and Grand Duke of Lithuania during the era of the Polish–Lithuanian Commonwealth, Duke of Opole in Upper Silesia, and titular King of Sweden 1648–1660. In Poland, he is known and commonly referred as Jan Kazimierz. His parents were Sigismund III Vasa (1566–1632) and Constance of Austria (1588–1631). His older brother, and predecessor on the throne, was Władysław IV Vasa. [END] 
Answer: 
Constance of Austria
Constance of Austria