Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia 3rd Duke Of Medina Sidonia (1464–1507) Parents Doña Leonor de Mendoza Enrique de Guzmán, 2nd Duke of Medina Sidonia Children Pedro Pérez de Guzmán, 1st Count of Olivares Juan Alfonso Pérez de Guzmán, 6th Duke of Medina Sidonia Enrique Pérez de Guzmán, 4th Duke of Medina Sidonia Alfonso Pérez de Guzmán, 5th Duke of Medina Sidonia Partners Isabel de Velasco y Mendoza