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Stibor (Scibor, Czibor) the younger's grave monument (died 1434) in Budapest History Museum
Budapesti Torteneti Muzeum (Budapest History Museum)

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Early 15th century relief of King Stibor II of Bolondoc. Stonework that once stood in the Matthias Church of Buda(pest), but was found in the former King Sigismund Castle at the Buda Height, Hungary

Tombstone of Stibor the Younger
1434
Red marble, 218 x 208 cm
Historical Museum, Budapest

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The tombstone type with coat-of-arms was formed at the end of 14th century and remained dominant until the 1460s. From the first half of 15th century only three tombstones with figural decoration survived, among them the tombstones of Voivode Stibor (+1414) in Szekesfehervar and his son, Stibor the Younger (+1434) in Buda.

Сцибор Младший герба Остоя, сын Сцибора из Сцибожице (Штибора из Штиборка), воевода Трансильвании. 1434 г.Надгробная плита определена как работа т.н. "Мастера надгробия Штибора". Исторический музей, Будапешт, Венгрия.

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Clan Ostoja (ancient Polish: Ostoya) was a powerful group of knights and lords in late-medieval Europe. The Clan encompass families in the Polish-Lithuanian Commonwealth, Upper Hungary (Slovakia), Hungary, Transylvania, Belarus, Ukraine, and Prussia. The Clan crest is the Ostoja coat of arms, and the battle cry is Ostoja ("Mainstay") or Hostoja. The Clan adopted the Royal-Sarmatian tamga draco (dragon) emblem.

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Stibor of Beckov the younger's grave monument, Budapest History Museum
Stibor of Stiboricz died in 1414 and was supposedly laid to rest in his own chapel inside St. Katarina's Church in Krakow. This was also supposedly the resting place for his son. It was also written that both father and son were buried in the chapel until 1903 when a grave of red marble stone was found in Buda. This was of Stibor Stiboric of Beckov, dated to 1431. In recent times, a grave was found in Szekesfehervar which had been broken into pieces as a result of Turkish destruction. However, it has now been established that this was the grave of Stibor of Stiboricz. It was made of the same stone, red marmor and when the piece of coat of arms was finally found and there was no doubt. Stibor was granted a place beside other members of the Hungarian royalty.

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Beckov Castle (Slovak: Beckovsky hrad/Beckov; Hungarian: Beckoi var) is a castle in ruins located near the village of Beckov in Nove Mesto nad Vahom District, Trencin Region, western Slovakia
In 1388, the castle was given by Sigismund, King of Hungary to Stibor of Stiboricz of the Clan of Ostoja, a Lord of Polish origin. Stibor was one of king's most influential advisors and in control of significant part of Northern Hungary (today, Slovakia). Of 31 Castles that was in possession of Stibor, he chose Beckov as his home, giving the Castle special care.
After Stibor's death in 1414, the castle was inherited by his son, Stibor Stiboric of Beckov

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перев. - найдена на месте средневекового кладбища при перестройке Успенской церкви в Буде
И. Стибор был Трансильванским воеводством († 1414) сын. На северо-западной границе страны он был назван «властелином реки Вах» (1414–1421), затем «капитаном» (1428) и участвовал в походе против гуситов как правитель царствования. Тот же надгробный камень назван тем же мастером скульптор, который лепил фрагмент саркофага своего отца в Секешфехерваре а также сделал надгробную плиту для другой женщины-члена семьи в Буде - все основано на их стиле в начале 1430-х годов, вероятно, по заказу бездетного Стибора, вероятно, в связи с его волей 1431 года.

Предполагается, что наш персонаж был похоронен вместе с отцом "in his own chapel inside St. Katarina's Church in Krakow" (эта семья происходит из Польши, но большую часть жизни прожили в Венгрии). В 1903 этот памятник нашего персонажа был найден в Буде. А недавно в Szekesfehervar (Венгрия) были найдены осколки аналогичного памятника, определенного позже как памятник отца нашего персонажа. Поэтому однозначно определить, где первоначально находились памятники, невозможно.
Основной зацепкой является замок Beckov, выбранный отцом нашего персонажа как дом для проживания. Наш персонаж унаследовал этот замок и стал зваться "of Beckov".