He had no legitimate children but a son out of wedlock named Jaime of Aragon, to whom his father gave the barony of Arenós and other places.

He was pretender to the throne of the Crown of Aragon during the Caspe Compromise after the death of his father claiming a better right to the throne being a straight male descendant of King Jaime II of Aragon, but he had very little support and finished in the final vote without any vote in his favor.

He fought beside Fernando of Antequera, who was elected King of Aragon, during the siege of Balaguer when Jaime II of Urgell, one of the pretenders to the throne, revolted against King Fernando, blocking the city gates of Lleida, and negotiating the surrender of the rebels.

Alfonso the younger prompted the construction of important monuments such as the Monastery of Sant Jeroni de Cotalba and the Ducal Palace of Gandía, which were formerly initiated by his father Alfonso of Aragon and Foix, the elder.

After his death without legitimate descendants, came a lawsuit on the succession of his territories, which was resolved temporarily by giving Gandia to his nephew Hugo Cardona and Ribagorza.