Sancho Alfonso, 1st Count of Alburquerque Illegitimate son of Alfonso XI of Castile (1342–1374) Parents Eleanor de Guzmán Alfonso XI of Castile and Leon Children Leonor Sánchez de Castilla Fernando de Castela, Conde de Alburquerque Eleanor of Alburquerque Siblings Fernando Alfonso de Castilla Juan Alfonso de Castilla Juana Alfonso de Castilla Pedro Alfonso de Castilla Tello de Castilla, Lord of Aguilar de Campoo Pedro de Aguilar Sancho Alfonso de Castilla Henry II of Castile Peter of Castile Fadrique Alfonso, Lord of Haro Partners NN Beatrice, Countess of Alburquerque