Question: Who was the second wife Sigismund I the Old, the King of Poland and Grand Duke of Lithuania and mother of Anna Jagiellon?
Sentence (from "Anna Jagiellon"): After the death of King Sigismund II Augustus, her brother and the last male member of the Jagiellon dynasty, Anna's hand was sought by pretenders to the Polish–Lithuanian throne to maintain the dynastic tradition.
Relevant evidence: No