Daughter of António Mendo Graça Caldeira de Castel-Branco (b. Oeiras e São Julião da Barra, Oeiras, 5 March 1949), patrilineal great-grandson and great-grandson of a first cousin of the 1st Viscount of Alter do Chão and great-grandson of a sister and great-grandson of a cousin of the 1st Baron of Brissos, and former wife TV presenter Luísa Castel-Branco (Maria Luísa Pires Pereira da Costa) (b. Santa Isabel, Lisbon, 12 April 1954).
