Agnes of Aquitaine, Queen of Aragon and Navarre
Agnes of Aquitaine( end of 1072 – 6 June 1097) was a daughter of William VIII, Duke of Aquitaine, and his third wife, Hildegarde of Burgundy, and thus half- sister of Agnes of Aquitaine, Queen of Castile, with whom she is sometimes confused.
In 1081, Agnes was betrothed to Peter I of Aragon and Navarre.
During 1086 in Jaca the couple married, and upon Peter's succession, Agnes became queen of Aragon and Navarre.
By him, Agnes had two children, both of whom predeceased their father: Peter( died 1103) and Isabella( died 1104).
Agnes died in 1097, and her husband remarried to a woman named Bertha.
Yolande Louise of Savoy
Yolande Louise of Savoy( 1487–1499), was a Duchess Consort of Savoy; married to Philibert II, Duke of Savoy.
Agnes of Aquitaine, Countess of Savoy
Agnes of Aquitaine (c.1052 – after 18 June 1089) was a daughter of William of Poitou, speculated to be William VII, Duke of Aquitaine, whose wife Ermesinde would then have been her mother.
Agnes herself was Countess consort of Savoy and possibly Queen consort of Aragon.
Agnes of Faucigny
Agnes of Faucigny( died 11 August 1268) was" suo jure" ruling Dame of Faucigny from 1253, as well as countess consort of Savoy by marriage to Peter II, Count of Savoy.
Adelaide, Countess of Burgundy
Adelaide of Merania( or Alice, Alix — died 8 March 1279, Évian) was Countess of Burgundy from 1248 until her death.
She was also Countess of Savoy and Bresse through her marriage in 1267 to Philip I, Count of Savoy.
Beatrice of Viennois
Beatrice of Vienne( 1160 –1230) was a Countess of Savoy by marriage to Humbert III, Count of Savoy.
Agnes of Burgundy, Duchess of Aquitaine
Agnes of Burgundy( or Agnes de Macon; died 10 November 1068) was Duchess of Aquitaine by marriage to Duke William V and Countess of Anjou by marriage to Count Geoffrey II.
She served as regent of the Duchy of Aquitaine during the minority of her son from 1039 until 1044.
She was a daughter of Otto- William, Count of Burgundy and Ermentrude de Roucy and a member of the House of Ivrea.
William VII, Duke of Aquitaine
William VII (born Peter, "Pierre-Guillaume") (1023 – autumn 1058), called the Eagle ("Aigret") or the Bold ("le Hardi"), was the duke of Aquitaine and count of Poitou (as William V) between 1039 and his death, following his half-brother Odo.
William was the third son of William V of Aquitaine, the eldest by his third wife, Agnes of Burgundy.
He was brother-in-law of the Holy Roman Emperor Henry III, who married his sister Agnes.
His mother remarried to Geoffrey Martel, Count of Anjou, during his reign.
William won his patrimony in a war with his half-brother Odo, who was killed in battle at Mauzé.
He did not, however, succeed in occupying Gascony.
Geoffrey Martel refused to concede to him the territories gained in the reigns of his predecessors.
William set to work regaining his patrimony by force of arms.
He was besieging Geoffrey in Saumur when he died of dysentery.
He was married to Ermesinde, of unknown origins.
Two daughters have been hypothesized to be children of this couple:
Philippa, Countess of Toulouse
Philippa( c. 1073 – 28 November 1118) was" suo jure" Countess of Toulouse, as well as the Duchess of Aquitaine by marriage to Duke William IX of Aquitaine.
Agnes of Waiblingen
Agnes of Waiblingen( 1072/ 73 – 24 September 1143), also known as Agnes of Germany, Agnes of Poitou and Agnes of Saarbrücken, was a member of the Salian imperial family.
Through her first marriage, she was Duchess of Swabia; through her second marriage, she was Margravine of Austria.

Question: What is the cause of death of Agnes Of Aquitaine, Countess Of Savoy's father?
Answer: dysentery