Joan of Navarre (regent)
Joan of Navarre( 1382 – July 1413) was the heir presumptive to the throne of Navarre in 1402 – 1413, and regent of Navarre in the absence of her father in 1409 – 1411.
She was the eldest child of King Charles III of Navarre by his wife Eleanor, daughter of King Henry II of Castile.
Alfonso VII of León and Castile
Alfonso VII (1 March 110521 August 1157), called the Emperor ("el Emperador"), became the King of Galicia in 1111 and King of León and Castile in 1126.
Alfonso, born Alfonso Raimúndez, first used the title Emperor of All Spain, alongside his mother Urraca, once she vested him with the direct rule of Toledo in 1116.
Alfonso later held another investiture in 1135 in a grand ceremony reasserting his claims to the imperial title.
He was the son of Urraca of León and Raymond of Burgundy, the first of the House of Ivrea to rule in the Iberian peninsula.
Alfonso was a dignified and somewhat enigmatic figure.
His rule was characterised by the renewed supremacy of the western kingdoms of Christian Iberia over the eastern (Navarre and Aragón) after the reign of Alfonso the Battler.
Though he sought to make the imperial title meaningful in practice to both Christian and Muslim populations, his hegemonic intentions never saw fruition.
During his tenure, Portugal became "de facto" independent, in 1128, and was recognized as "de jure" independent, in 1143.
He was a patron of poets, including, probably, the troubadour Marcabru.
Sancha of León
Sancha of León( 8 November 1067) was a Queen of León.
Sancha of Castile, Queen of Navarre
Sancha of Castile (–1179) was daughter of Alfonso VII of León and Castile and his first wife Berengaria of Barcelona.
Sancha was the fifth child of seven born to her parents.
On 20 July 1153, Sancha married Sancho VI of Navarre.
He is responsible for bringing his kingdom into the political orbit of Europe.
As "la reyna de Navarra, filla del emperador" (the queen of Navarre, daughter of the Emperor)
her August 1179 death was reported in the "Annales Toledanos".
Eleanor of Aragon, Countess of Toulouse
Eleanor of Aragon, Countess of Tolouse( 1182–1226) was a daughter of King Alfonso II of Aragon and Sancha of Castile, Queen of Aragon.
She married Raymond VI, Count of Toulouse.
René I, Viscount of Rohan
René I de Rohan,( 1516–1552) 18th Viscount of Rohan, Viscount and Prince de Léon, and Marquis de Blain married Isabella of Navarre daughter of jure uxoris King John III of Navarre and Catherine of Navarre, Queen of Navarre.
Isabella of Navarre, Viscountess of Rohan
Isabel d' Albret of Navarre( 1512–1555) was the daughter of John III of Navarre( died 1516) and Catherine I of Navarre, sister and heiress of Francis Phoebus, King of Navarre.
As heir apparent, her brother rose to the throne in 1517 as Henry II of Navarre, grandfather of King Henry III of Navarre( Henry IV of France).
Eleanor of Castile, Queen of Navarre
Eleanor of Castile( after 1363 – 27 February 1416) was an infanta of Castile and the Queen consort of Navarre.
She was the daughter of King Henry II of Castile and his wife, Juana Manuel of Castile, from a cadet branch of the Castilian royal house.
Eleanor was a member of the House of Trastámara.
Beatrice of Navarre, Countess of La Marche
Beatrice of Navarre( 1392-1412/1415) was a daughter of Charles III of Navarre and his wife, Eleanor of Castile.
Blanche of Navarre, Countess of Champagne
Blanche of Navarre( ?–1229) was countess and then regent of Champagne and finally also regent of her native kingdom of Navarre.
She was the youngest daughter of Sancho VI of Navarre and Sancha of Castile, who died in 1179, about two years after Blanche's birth.
Her eldest brother, Sancho VII of Navarre, succeeded their father as King of Navarre and was the last male descendant of the first dynasty of Kings of Navarre, the Pamplona dynasty, dying childless.
Her elder sister Berengaria of Navarre married Richard I of England.

Question: Who is Sancha Of Castile, Queen Of Navarre's paternal grandfather?
Answer: Raymond of Burgundy