Bernardino Fernández de Velasco, 1st Duke of Frías
Don Bernardino Fernández de Velasco, 1st Duke of Frías, Grandee of Spain( c. 1450 – 9 February 1512) was a Spanish nobleman and prominent military figure of the last stages of the Reconquista.
Fernández de Velasco was born in Burgos, the son of Don Pedro Fernández de Velasco, 2nd Count of Haro, Constable of Castille, and of Doña Mencía de Mendoza y Figueroa, herself a daughter of the illustrious Marquis of Santillana.
He participated in the conquest of Granada, where his father died, and became one of its firsts Viceroys.
On 20 March 1492 he was granted the title of Duke of Frías by the Catholic Monarchs.
He first married Doña Blanca de Herrera, Lady of Pedraza de la Sierra, with whom he had a daughter, Ana Herrera de Velasco, who married the Count- Duke of Benavente.
After becoming a widow, he married secondly Doña Juana de Aragón, Lady of Castilnovo, an illegitimate daughter of King Ferdinand II of Aragon, with whom he had another daughter, Doña Juliana de Velasco y Aragón, 1st Countess of Castilnovo, and future consort Duchess of Frías by her marriage to her cousin.
He had no legitimate male issue, so his titles passed on to his younger brother Don Íñigo Fernández de Velasco, 2nd Duke of Frías.
Bernardino de Cárdenas y Portugal, Duque de Maqueda
Bernardino de Cárdenas y Portugal (Torrijos, 20 January 1553 – Palermo, 17 December 1601), 3rd Duke of Maqueda, 2nd Marquis of Elche, was a Spanish noble and statesman.
He was the son of Bernardino de Cárdenas y Pacheco, 2nd Duke of Maqueda, 1st Marquis of Elche, and of Isabel de Velasco, daughter of Íñigo Fernández de Velasco, 2nd Duke of Frías, Constable of Castille.
He was viceroy of Catalonia and of Sicily.
He married Luisa Manrique de Lara, 5th Duchess of Nájera and had 4 sons and 2 daughters.<br>
He was succeeded by his eldest surviving son Jorge de Cárdenas y Manrique de Lara.
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Pedro Fernández de Velasco, 3rd Duke of Frías
Pedro Fernández de Velasco, 3rd Duke of Frías( c. 1485 – 10 November 1559), Grandee of Spain( in full) was a Spanish nobleman.
Fernández de Velasco was the son of Íñigo Fernández de Velasco, 2nd Duke of Frías and of Doña María de Tovar, Lady of Berlanga.
He married his cousin Doña Juliana de Velasco y Aragón, 1st Countess of Castilnovo, daughter of Bernardino Fernández de Velasco, 1st Duke of Frías in 1508, but they had no issue.
He succeeded as 3rd Duke of Frias in 1528.
After 1559, Pedro's nephew, Iñigo, was known as Iñigo II Fernandez de Velasco, 4th Duke of Frias.
Enrique Pérez de Guzmán, 4th Duke of Medina Sidonia
Don Enrique Pérez de Guzmán y Fernández de Velasco, 4th Duke of Medina Sidonia( died 1512) was the son of Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia.
He was Duke of Medina Sidonia from 1507.
No issue by his wife María Téllez Girón.
Íñigo Fernández de Velasco, 2nd Duke of Frías
Íñigo Fernández de Velasco, 2nd Duke of Frías, Grandee of Spain,( in full),( 1462–17 September 1528), was a Spanish nobleman and Duke of Frias.
Fernández de Velasco was the son of Pedro Fernández de Velasco and of Mencía de Mendoza y Figueroa, and he inherited the titles from his older brother Bernardino, who had no legitimate male issue.
He married María de Tovar, Lady of Berlanga, with whom he had six children.
He took part in the Castilian War of the Communities, and led the royalist army to victory at the Battle of Villalar.
Íñigo Melchor de Velasco, 7th Duke of Frías
Íñigo Melchor Fernández de Velasco, 7th Duke of Frías, GE, KOS( 16 April 1629 – 27 September 1696), was a Spanish nobleman and Governor- General of the Spanish Netherlands.
Juan Sancho de Tovar, 1st Marquis of Berlanga
Juan Sancho de Tovar, 1st Marquis of Berlanga (in full)  was a Spanish nobleman.
Tovar was the second son of Íñigo Fernández de Velasco, 2nd Duke of Frías and of María de Tovar, Lady of Berlanga.
His original name was "Juan Sancho Fernández de Velasco y Tovar", but he changed it and adopted his mother's last name in order to succeed to her titles, as Lord of Berlanga.
On 10 April 1529, he was raised to Marquis of Berlanga by Charles V, Holy Roman Emperor.
He married María Girón, Lady of Gandul and Marchenilla, with whom he had 8 children.
After the death of his first wife, he married Juana Enríquez, sister of Perafán de Ribera, 1st Duke of Alcalá.
They had no issue.
Tovar died in 1540.
Juan Téllez-Girón, 2nd Duke of Osuna
Juan Téllez- Girón, 2nd Duke of Osuna, Grandee of Spain,( in full),( 20 Octubre 1559 – 25 November 1600), was a Spanish nobleman.
Juan Téllez- Girón was the son of Pedro Girón, 1st Duke of Osuna and of Leonor Ana de Guzmán y Aragón( c.1540–23 November 1573), daughter of Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia.
In 1570, he married his cousin Ana María de Velasco, daughter of Íñigo Fernández de Velasco, 4th Duke of Frías, with whom he had 5 children.
Juan Fernández de Velasco, 5th Duke of Frías
Juan Fernández de Velasco, 5th Duke of Frías( – 15 March 1613) was a Spanish nobleman and diplomat.
Íñigo Fernández de Velasco, 4th Duke of Frías
Íñigo Fernández de Velasco, 4th Duke of Frías, Grandee of Spain, (in full), (– 1585), was a Spanish nobleman.
Fernández de Velasco was the son of Juan Sancho de Tovar, 1st Marquis of Berlanga and of María Girón, Lady of Gandul and Marchenilla.
His original name was "Íñigo de Tovar y Velasco", but he changed it and re-adopted his father's original last name when he inherited the Dukedom of Frías from his uncle Pedro Fernández de Velasco, who had no issue.
He married Ana Pérez de Guzmán
y Aragón, daughter of Juan Alfonso Pérez de Guzmán, 6th Duke of Medina Sidonia, with whom he had eleven children, among whom Juan Fernández de Velasco, 5th Duke of Frías.

Question: Who is Íñigo Fernández De Velasco, 4Th Duke Of Frías's paternal grandfather?