Kaya Alp
Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
Blanche of Bourbon
Blanche of Bourbon( 1339 – 1361) was Queen of Castile as the wife of King Peter.
She was one of the daughters of Peter I, Duke of Bourbon and Isabella of Valois.
Bonne of Bourbon
Bonne of Bourbon( 1341 – 19 January 1402) was a daughter of Peter I, Duke of Bourbon, and Isabella of Valois, and hence a sister of Joanna of Bourbon.
She served as regent of Savoy during the absence of her spouse from 1366 to 1367, in 1383, and during the minority of her grandson Count Amadeus VIII in 1391.
Mathilde of Bourbon
Mathilde of Bourbon( – 18 June 1228) was a French noblewoman who was the ruling Lady of Bourbon from 1171 until her death.
Charles I, Duke of Bourbon
Charles de Bourbon (1401 – 4 December 1456, Château de Moulins) was the oldest son of John I, Duke of Bourbon and Marie, Duchess of Auvergne.
He was Count of Clermont-en-Beauvaisis from 1424, and Duke of Bourbon and Auvergne from 1434 to his death, although due to the imprisonment of his father after the Battle of Agincourt, he acquired control of the duchy more than eighteen years before his father's death.
In 1425, Charles renewed his earlier betrothal by marrying Agnes of Burgundy (1407–1476), daughter of John the Fearless.
Charles entered a relationship with Jeanne de Bournan, together they had Louis de Bourbon, Count of Roussillon.
Louis founded the House of Bourbon-Roussillon (Rossello).
Louis is known for his many services to the State.
As a reward for his loyalty and dedication to Louis XI during the League of the Public Weal conflict, Louis XI gave him in marriage his legitimized daughter Jeanne de Valois.
Charles served with distinction in the Royal army during the Hundred Years' War, while nevertheless maintaining a truce with his brother-in-law and otherwise enemy, Philip III, Duke of Burgundy.
Both dukes were reconciled and signed an alliance by 1440.
He was present at the coronation of Charles VII where he fulfilled the function of a peer and conferred knighthood.
Despite this service, he took part in the "Praguerie" (a revolt by the French nobles against Charles VII) in 1439–1440.
When the revolt collapsed, he was forced to beg for mercy from the King, and was stripped of some of his lands.
He died on his estates in 1456.
Isabella of France, Dauphine of Viennois
" For other persons named Isabella of France, see Isabella of France( disambiguation)" Isabella of France and Burgundy( 1310 – April 1348) was the daughter of Philip V of France and Joan II, Countess of Burgundy.
Isabella of Bourbon
Isabella of Bourbon, Countess of Charolais (1434 – 25 September 1465) was the second wife of Charles the Bold, Count of Charolais and future Duke of Burgundy.
She was a daughter of Charles I, Duke of Bourbon and Agnes of Burgundy, and the mother of Mary of Burgundy, heiress of Burgundy.
Tahira Wasti
Tahira Wasti( 1944 – March 11, 2012) was a well- known Pakistani writer and television actress.
She is best known for portrayal of Isabella of Castile in the TV drama" Shaheen".
Isabella of Valois, Duchess of Bourbon
Isabella of Valois, Duchess of Bourbon or" Isabella of France"( 1313 – 26 July 1383), was a Petit Fille of France, and a daughter of Charles of Valois by his third wife Mahaut of Châtillon.
She was the wife of Peter I, Duke of Bourbon.
Beatrice of Bourbon, Queen of Bohemia
Beatrice of Bourbon( 1320 – 23 December 1383) was a French noblewoman.
A member of the House of Bourbon, she was by marriage Queen of Bohemia and Countess of Luxembourg.
She was the youngest daughter of Louis I, Duke of Bourbon, and Mary of Avesnes.

Question: Who is Isabella Of Bourbon's paternal grandfather?
Answer: John I, Duke of Bourbon