Who married Michael Žygimantaitis?

Michael Žygimantaitis (Lithuanian: Mykolas Žygimantaitis; Polish: Michał Bolesław Zygmuntowicz; before 1406 – shortly before February 10, 1452) was a pretender to the throne of the Grand Duchy of Lithuania and the last male descendant of Kęstutis, Grand Duke of Lithuania.

Catherine of Masovia (Polish: Katarzyna mazowiecka; 1413/16 – between 2 June 1479 and 5 July 1480) was a Polish princess member of the House of Piast in the Masovian branch.

She was the eighth and youngest daughter of Siemowit IV, Duke of Masovia and Alexandra, a daughter of Algirdas, Grand Duke of Lithuania and sister of King Władysław II Jagiełło of Poland.

Eufemia mazowiecka (ur. 1415/1418, zm. między 7 lutego 1435 a 3 marca 1436) – księżniczka mazowiecka z dynastii Piastów.