Alfonso II of Aragon
Alfonso II (1–25 March 1157 – 25 April 1196), called the Chaste or the Troubadour, was the King of Aragon and, as Alfons I, the Count of Barcelona from 1164 until his death.
The eldest son of Count Ramon Berenguer IV of Barcelona and Queen Petronilla of Aragon, he was the first King of Aragon who was also Count of Barcelona.
He was also Count of Provence, which he conquered from Douce II, from 1166 until 1173, when he ceded it to his brother, Ramon Berenguer III.
His reign has been characterised by nationalistic and nostalgic Catalan historians, as "l'engrandiment occitànic" or "the Pyrenean unity": a great scheme to unite various lands on both sides of the Pyrenees under the rule of the House of Barcelona.
Constance of Aragon, Lady of Villena
Constance of Aragon( 1239 – 1269) was a daughter of James I of Aragon and his second wife Yolanda of Hungary.
She was a member of the House of Barcelona and was Infanta of Castile by her marriage to Manuel of Castile.
Her maternal grandparents were Andrew II of Hungary and his second wife Yolanda de Courtenay.
Her paternal grandparents were Peter II of Aragon and Marie of Montpellier.
Constance's siblings included: James II of Majorca, Peter III of Aragon, Yolanda, Queen of Castile and Isabella, Queen of France.
In 1260 and in Soria, Constance married" Infante" Manuel of Castile, the second son of Ferdinand III and his first wife Elisabeth of Hohenstaufen.
The couple had at least two children:
Constance died in 1269, leaving her husband a widower.
He remarried in 1274/ 5 to Beatrice of Savoy.
Their son was Juan Manuel, Prince of Villena, who was successor to his father since Constance's son, Alfonso died young.
Eleanor of Aragon, Queen of Castile
Eleanor of Aragon (20 February 1358 – 13 August 1382) was a daughter of King Peter IV of Aragon and his wife Eleanor of Sicily.
She was a member of the House of Aragon and Queen of Castile by her marriage.
Eleanor of Castile (died 1244)
Eleanor of Castile( 1200 – 1244) was a daughter of Alfonso VIII of Castile and Eleanor of England.
She was Queen consort of Aragon by her arranged marriage to James I of Aragon.
Her mother was a daughter of Henry II of England and Eleanor of Aquitaine.
Eleanor's sister Berengaria became Queen of Castile since their brother Henry I of Castile died with no issue and because Berengaria was the eldest of the daughters.
Another sister, Blanche became Queen of France by her marriage to Louis VIII of France.
Constance of Aragon
Constance of Aragon( 1179 – 23 June 1222) was an Aragonese infanta who was by marriage firstly Queen of Hungary, and secondly Queen of Germany and Sicily and Holy Roman Empress.
She was regent of Sicily from 1212 – 1220.
She was the second child and eldest daughter of the nine children of Alfonso II of Aragon and Sancha of Castile.
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.
Sancha of Aragon, Countess of Toulouse
Sancha of Aragon( 1186–1241) was the daughter of King Alfonso II of Aragon and his wife, Sancha of Castile.
Through her marriage to Raymond VII, Count of Toulouse in 1211, she acquired the titles Countess of Toulouse and Marquise of Provence from then until their divorce in 1241.
Sancha's paternal grandparents were Ramon Berenguer IV, Count of Barcelona and Petronilla of Aragon; her maternal grandparents were Alfonso VII of León and Castile and Richeza of Poland, Queen of Castile.
She was the sister of Peter II of Aragon and Alfonso II, Count of Provence.
She had one child, Joan, Countess of Toulouse, who held the same titles as her mother from 1249 to 1271.
Sancha of Castile, Queen of Aragon
Sancha of Castile (21 September 1154/5 – 9 November 1208) was the only surviving child of King Alfonso VII of Castile by his second wife, Richeza of Poland.
On January 18, 1174, she married King Alfonso II of Aragon at Zaragoza; they had at least eight children who survived into adulthood.
A patroness of troubadours such as Giraud de Calanson and Peire Raymond, the queen became involved in a legal dispute with her husband concerning properties which formed part of her dower estates.
In 1177 she entered the county of Ribagorza and took forcible possession of various castles and fortresses which had belonged to the crown there.
After her husband died at Perpignan in 1196, Sancha was relegated to the background of political affairs by her son Peter II.
She retired from court, withdrawing to the Hospitaller convent for noble ladies, the Monastery of Santa María de Sigena, at Sigena, which she had founded.
There she assumed the cross of the Order of St John of Jerusalem which she wore until the end of her life.
The queen mother entertained her widowed daughter Constance at Sigena prior to her leaving Aragon to marry Emperor Frederick II in 1208.
She died soon afterwards, aged fifty-four, and was interred in front of the high altar of her foundation at the Monastery of Santa María de Sigena; her tomb is still there to be seen.
Sancha of León
Sancha of León( 8 November 1067) was a Queen of León.
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.

Question: Who is Sancha Of Castile, Queen Of Aragon's father-in-law?
Answer: Ramon Berenguer IV