Who was married to Sigismund III Vasa, and mother to Władysław IV Vasa?
John II Casimir Vasa 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.
Ladislaus IV of Hungary Ladislaus the Cuman (Hungarian: "IV. (Kun) László" , Croatian: "Ladislav IV. Kumanac" , Slovak: "Ladislav IV. Kumánsky" ; 5 August 1262 – 10 July 1290), also known as Ladislas the Cuman, was king of Hungary and Croatia from 1272 to 1290. His mother, Elizabeth, was the daughter of a chieftain from the pagan Cumans who had settled in Hungary. At the age of seven, he married Elisabeth (or Isabella), a daughter of King Charles I of Sicily. Ladislaus was only 10 when a rebellious lord, Joachim Gutkeled, kidnapped and imprisoned him.