Juan de Velasco La Cueva y Pacheco, 8th Count of Siruela, a title awarded initially by king Henry IV of Castile in 1470, Governor of the Duchy of Milan, 1641–1643, deceased 1651, no issue, was one of the 11 children born from the 7th Count, Gabriel, and Victoria Pacheco y Toledo-Colonna, an orphan daughter of Juan Pacheco, 2nd marquis of Cerralbo, deceased 1589 when traveling to Flanders. This compounded name we use, de Velasco La Cueva comes from the 3rd Countess of Siruela, Leonor, deceased 1529, who had married in 1505, her "more aristocratic husband", Cristóbal de la Cueva y Velasco, deceased 1542, the son of highly conflictive Beltran de la Cueva, 1st Duke of Albuquerque, deceased 1492, and his 3rd wife, Maria de Velasco, 1st Duchess of Roa.
Although the Counts of Siruela splashed since, all around, their "de Velasco" family name to impress unaware people using their "de Velasco" family name putting behind, compounding it, with the "La Cueva" family name of the 3rd Countess of Siruela obliging husband, Cristóbal, we can conclude today that the grade of connection either with Dukes of Albuquerque, named "La Cueva" for many generations, or with the ducal branch of the "de Velasco" was always rather tenuous.
Further, 4 of these 11 children would become in due time, through the death of brothers/sisters counts or countesses of Siruela, namely, Juan, deceased around 1650, Gaspar, 9th Count, deceased around 1651, Ana María, X Countess, (death date unknown), and Leonor, XI Countess, who died single, no issue, in 1689. The 12th Count would be a relative, named as Cristóbal de Velasco La Cueva y Carrillo de Mendoza, (1621 - married 1655 - June 1692), from Cuenca.