Alfonso II, Duke of Gandia
Alfonso of Aragon and Eiximenis, also known as Alfonso II of Gandia" the young" or Alfonso V of Ribagorza( c. 1358 – 31 August 1422) Duke of Gandia, count of Denia and count of Ribagorza, was the son of Alfonso of Aragon and Foix and his wife Violante Jimenez.
He married María of Navarra, daughter of Carlos II of Navarre, on January 20, 1393 in Tudela, Navarra.
After her death, he contracted a second marriage with Violant of Villafeliche.
He had no legitimate children but a son out of wedlock named Jaime of Aragon, whom his father inherited with the barony of Arenós and other places.
He was pretender to the throne of the Crown of Aragon during the Caspe Compromise after the death of his father claiming a better right to the throne being descendant by King Jaime II of Aragon male straight, but had very little support and finished the final vote without any vote in his favor.
He fought beside Fernando of Antequera, who was elected King of Aragon, during the siege of Balaguer when Jaime II of Urgell, one of the pretenders to the throne, revolted against King Ferdinand, blocking the city portal of Lleida, and negotiating the surrender of the rebels.
Alfonso" the younger" prompted the construction of important monuments such as the Monastery of Sant Jeroni de Cotalba and the Ducal Palace of Gandía, which were formerly initiated by his father Alfonso of Aragon and Foix," the old".
On his death without legitimate descendants came a lawsuit by the succession of their territories, which was resolved temporarily giving Gandia to Hugo Cardona and Ribagorza.
A few years later, in 1433, Hugo de Cardona Juan II of Aragon must cede the Duchy of Gandia the infant Juan of Aragon, future.
In this way they returned to join the titles of Duke of Gandia and count of Ribagorza.
Maria of Aragon, Queen of Castile
Maria of Aragon was the Queen consort of Castile and Leon as the wife of John II of Castile.
She was the daughter of Ferdinand I of Aragon and Eleanor of Alburquerque.
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.
Petronilla of Aragon
Petronilla( 29 June/ 11 August 1136 – 15 October 1173), whose name is also spelled Petronila or Petronella( Aragonese" Peyronela" or" Payronella", and), was the Queen of Aragon from the abdication of her father in 1137 until her own abdication in 1164.
She was the daughter and successor of Ramiro II by his queen, Agnes.
She was the last ruling member of the Jiménez dynasty in Aragon, and by marriage brought the throne to the House of Barcelona.
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.
Felicia of Roucy
Felicia of Roucy (– 3 May 1123) was a queen consort of Aragon and Navarre.
She was a daughter of Hilduin IV of Montdidier and his wife Alice of Roucy.
She was married in 1076 to Sancho Ramírez, then king of Aragon after he had divorced his first wife, Isabella of Urgell.
His accession to the crown of Navarre later that year made her the first Aragonese consort to also be Queen consort of Navarre.
She is attested shortly before her husband's death and is now thought to have outlived Sancho (the supposed subsequent marriage of Sancho to a third wife, Philippa of Toulouse, appearing in a later chronicle, is now thought to be erroneous).
Felicia gave birth to three sons, Ferdinand, Alfonso and Ramiro, the latter two following her step-son Peter I of Aragon and Navarre in Aragon (Alfonso also in Navarre).
Through Ramiro's only daughter Petronila of Aragon, she was ancestor of the later rulers of Aragon.
Ramiro II of Aragon
Ramiro II (24 April 1086 – 16 August 1157), called the Monk, was King of Aragon from 1134 until withdrawing from public life in 1137 (although he used the royal title until his death).
He was the youngest son of Sancho Ramírez, King of Aragon and Navarre and Felicia of Roucy.
Abiathar Crescas
Abiathar Crescas was a 15th- century physician and astrologer from the Crown of Aragon( now part of Spain).
He was head astrologer to King John II of Aragon, father of King Ferdinand of Aragon.
He could remove cataracts by a surgical procedure known as couching.
In 1468 he restored the eyesight of King John in two simple operations, who was completely blind before the surgeries.
Crescas was a leader of Aragon's Jewish community.
Isabella of Aragon, Queen of Germany
Isabella of Aragon( 1305 – 12 July 1330) was the daughter of James II of Aragon and his second wife Blanche of Anjou.
Queen consort of Frederick I of Austria.
She was a member of the House of Aragon
Joanna of Aragon, Countess of Ampurias
Joanna of Aragon( Barcelona 7 November 1344- Castellón, Ampurias 1385) was the second child of Peter IV of Aragon and his first wife Maria of Navarre.
She was an Infanta of Aragon by birth and Countess of Ampurias by her marriage.
She was a member of the House of Aragon.

Question: Who is Ramiro Ii Of Aragon's maternal grandfather?
Answer: Hilduin IV of Montdidier