Isabel of Portugal, Lady of Viseu

Though, it was rumored at the time that her mother was none other than the king's half-sister, Beatrice, Countess of Albuquerque,[1] with whom he was said to have had an incestuous relationship according to the chronicler Fernão Lopes.

She married Alfonso Enríquez, Count of Gijón and Noreña, natural son of King Henry II of Castile.

Through a royal letter issued on 2 October 1377, her father granted her the Lordship of Viseu, Celorico, Linhares and Algodres.

She left to the Royal Court of King Henry II of Castile where she lived while waiting for an appropriate age to get married.

This marriage gave rise to the Noronha family, still represented in several aristocratic houses, both in Portugal and in Spain.