King Sigismund I the Old died on 1 April 1548. Sigismund Augustus, who briefly returned to Vilnius, had to travel back to Kraków to attend the funeral and secure himself on the Polish throne. Barbara stayed in Vilnius. It seems that around the same time Barbara informed him of another pregnancy; it too ended in a miscarriage. Since it is known only from Radziwiłł reports, it is unknown whether it was a real pregnancy or another intrigue. In September 1548, Sigismund Augustus invited Barbara to Poland to show the strength of their marriage. The issue was discussed by the general sejm on 31 October – 12 December in Piotrków Trybunalski. The sessions were loud and rowdy. The nobles, including voivodes Piotr Kmita Sobieński, Jan Gabriel Tęczyński, and Piotr Boratyński, pleaded the King to abandon the marriage and even threatened to take up arms. Sigismund Augustus steadfastly refused and stood by his wife; reportedly he even considered abdication. The sejm ended in a stalemate.