 His birth name was Frederick according to the Sicilian traditions, but according to the Aragonese customs he was baptized as Peter on 29 April 1399 at his birthplace Ursino Castle with great ceremony.The king and queen had been childless for a long time, so the birth of a son was a great joy not only for Kingdom of Sicily but for Kingdom of Aragon too.In Aragon he was second in line after his father.