Tvrtko I of Bosnia
It is known that Catherine was of Bosnian origin, but her parentage is disputed. Some believe that Catherine was the daughter of Vladislav Kotromanić and his wife Jelena Šubić. Others believe she was the second daughter of Stephen II, Ban of Bosnia, and his third wife Elizabeth of Kuyavia. If Catherine was a daughter of Stephen, she was the sister of Queen Elizabeth of Hungary; if she was a daughter of Vladislav, she was sister of King Tvrtko I of Bosnia.