Eleanor of Aragon
Eleanor of Aragon (20 January 1358 – 13 August 1382) was a daughter of King Peter IV of Aragon and his wife Eleanor of Sicily. Her brother became Juan I, King of Aragon. She was born at Santa Maria del Puig and died at Cuellar. On 18 June 1375, at Soria, she became queen of Castile by marrying King John I of Castile.
Their eldest son Enrique (1379–1406) became King Henry III of Castile and his twin brother Fernando (1380–1416) ultimately was elected to inherit Eleanor's native Aragon in 1412, becoming King Ferdinand I of Aragon.