the husband of Madeleine, a daughter of Charles VII of France, died in 1470, and when Gaston IV died two years later, his lands descended to his grandson, Francis Phoebus (died 1483). Francis Phoebus became king of Navarre in 1479 and was succeeded by his sister Catherine (died 1517), the wife of Jean d'Albret (d. 1516).

A younger son of Count Gaston IV was John