 Isabella ensured long-term political stability in Spain by arranging strategic marriages for each of her five children.Her firstborn, a daughter named Isabella, married Afonso of Portugal, forging important ties between these two neighboring countries and hopefully ensuring future alliance, but Isabella soon died before giving birth to an heir.Juana, Isabella's second daughter, married into the Habsburg dynasty when she wed Philip the Fair, the son of Maximilian I, King of Bohemia (Austria) and likely heir to the crown of the Holy Roman Emperor.