Article: In 1430 with the Privileges of Jedlnia, confirmed at Kraków in 1433 (Polish: "przywileje jedlneńsko-krakowskie"), based partially on his earlier Brześć Kujawski privilege (April 25, 1425), King Władysław II Jagiełło granted the nobility a guarantee against arbitrary arrest, similar to the English Magna Carta's Habeas corpus, known from its own Latin name as "neminem captivabimus (nisi jure victum)." Henceforth no member of the nobility could be imprisoned without a warrant from a court of justice: the king could neither punish nor imprison any noble at his whim. King Władysław's quid pro quo for this boon was the nobles' guarantee that his throne would be inherited by one of his sons (who would be bound to honour the privileges theretofore granted to the nobility). On May 2, 1447 the same king issued the Wilno Privilege which gave the Lithuanian boyars the same rights as those possessed by the Polish szlachta.

Question: What was the nobles guarantee that his throne would be inherited by his sons?
King Władysław's quid pro quo for this boon