Question: Who is Beatrice Of Castile (1242–1303)'s father-in-law?
Sentence (from "Beatrice of Castile (1242–1303)"): Beatrice of Castile (1242/1244 – 27 October 1303), an illegitimate daughter of Alfonso X of Castile and his mistress Mayor Guillén de Guzmán, was the second Queen consort of Afonso III of Portugal.
Relevant evidence: Yes