title of Prince of Asturias for the couple. This title was then passed to the successive heirs, no matter if they were males or females. By birth, the firstborns of the kings had the title of infante like their brothers and sisters, but when they were proclaimed as heirs before the Cortes, they then became Princes of Asturias.

The same happened in Navarre, when Charles III created for his grandson, the Infante Carlos,