en: His parents were John the `` Iron '' and his wife Helen of Lithuania , a niece of King Jogaila of Poland . His parents were John II `` the Iron '' and his wife Helen of Lithuania , a niece of King Jogaila of Poland .
ms: Ibu bapanya ialah John "Iron" dan isterinya Helen dari Lithuania, seorang anak saudara Raja Jogaila dari Poland. Ibu bapanya ialah John II `the Iron'' dan isterinya Helen dari Lithuania, seorang anak saudara Raja Jogaila dari Poland.