The Fondos of Parral has a file containing letters back and forth of Sebastian de Funes Villanueva's claim to 1000 silver pieces. Here are two pages that show a) Sebastian de Funes y Villanueva was also called Sebastian de Medina, 2) Sebastian is acknowledged to be the brother in law of Cristobal de Aguilera (his sister Cristina's husband) and c) Sebastian is referred to as the legitimate son of Alonso de Funes the brother of Diego de Ximenes y Funes and thus eligible to share in the inheritance of his grandfather and uncle.