The Livro Velho names "D. Fernão Mendes o bravo e Ruy Mendes" as the children of "D. Mem Fernandes" and his wife. 
  Senhor de Bragança de Langroiva e Noman (in Galicia).
  Married firstly ---. The possibility of an earlier, otherwise unrecorded, marriage is suggested by the logic used to explain the identity of Fernando´s known wife Sancha Henriques in light of the apparently contradictory sources.... 
  Married secondly Sancha Henriques, [separated wife of Sancho Núñez de Barbosa,] daughter of Henrique Conde de Portugal & his wife Teresa de Castilla Queen of Portugal.... 1