Theobald III, Count of Blois
Theobald III of Blois( French:" Thibaut")( 1012–1089) was count of Blois, Meaux and Troyes.
He was son of Odo II, Count of Blois and Ermengarde of Auvergne.
Adela of Normandy
Adela of Normandy, of Blois, or of England( c. 1067 – 8 March 1137), also known as in Roman Catholicism, was a daughter of William the Conqueror and Matilda of Flanders who later became the Countess of Blois, Chartres, and Meaux by marriage to Stephen II, Count of Blois.
Her husband greatly benefited from the increased social status and prestige that came with such a marriage.
She brought with her not only her bloodline, but a wedding gift of money and other movable goods from the prodigious store of Anglo- Norman wealth.
She was regent of Blois during the absence of her spouse in 1096 – 1100 and 1101 – 02, and during the minority of her son from 1102 until 1120.
Adela was the mother of Stephen, King of England and Henry of Blois, Bishop of Winchester.
The couple had ten children, though it is not certain if all were Adela's biological children.
It is only certain that she had five sons and might have had three or more daughters.
Alix of Brittany, Dame de Pontarcy
Alix of Brittany, Dame de Pontarcy, Countess of Blois (6 June 1243 – 2 August 1288), was a Breton noblewoman and a member of the House of Dreux as the eldest daughter of John I, Duke of Brittany.
She married John I, Count of Blois.
Alix was known for founding religious houses including the Monastery of La Guiche, where she was later buried.
Alix, named after her paternal grandmother, Alix of Thouars, was born on 6 June 1243 at the Château de Suscinio in Sarzeau, Morbihan, Brittany.
She was the eldest daughter of John I, Duke of Brittany and Blanche of Navarre, daughter of Theobald I of Navarre and Agnes of Beaujeu.
Alix held the title "Dame de Pontarcy" in her own right.
Sometime after a contract was signed on 11 December 1254, she married John I, Count of Blois of the House of Châtillon.
Thereafter she was styled Countess of Blois.
She brought as her dowry her titles of Pontarcy and de Brie-Comte-Robert, which had been named after her ancestor Robert I of Dreux.
The marriage produced one child, a daughter Jeanne, who was heiress to her father's title and estates.
In 1270, her husband was appointed Lieutenant General of France.
Through Alix's marriage to John, the Château de Brie-Comte-Robert passed to the Châtillon family.
Alix and John founded several religious houses including the Monastery of La Guiche near Blois in 1277.
She became a widow on 28 June 1279.
In 1287, the year before her own death, Alix travelled to Palestine.
From there she journeyed on to Syria, where she commissioned the erection of two barbican towers at Ptolemais.
Mary, Countess of Blois
Mary, Countess of Blois, also known as" Marie of Avesnes",( 1200 – 1241) was countess of Blois from 1230 to 1241.
She was the daughter of Walter of Avesnes and Margaret of Blois.
In 1226, Mary married Hugh I of Châtillon, a count from Châtillon- sur- Marne, son of Gaucher III of Châtillon and Elisabeth of Saint Pol.
They had five children:
Her eldest son John, succeeded her in Blois.
Margaret, Countess of Blois
Margaret of Blois( French:" Marguerite"; died 1230) was" suo jure" Countess of Blois from 1218 to 1230, in what is now France.
Joan, Countess of Blois
Joan of Châtillon ("Jeanne de Blois"; 1253? – 19 or 29 January 1291) was Countess of Blois from 1280 to 1291, and Lady of Avesnes.
She was the daughter of John I, Count of Blois and Alix of Brittany, Dame de Pontarcy.
Joan received the County of Chartres from her father during his life; she later sold these lands to Philip IV of France in 1286.
She ceded the lordship of Avesnes to her cousin Hugh before her death.
When she died in 1291 the other titles were left to him also.
In 1263, Joanne married Peter of Alençon, a son of King Louis IX of France and Margaret of Provence.
They had two sons who both died in infancy:
Joan died in 1291, with no living issue.
She left the title of Count of Blois and her remaining titles to her cousin Hugh.
Theobald II of Blois
Theobald II, Count of Blois( Thibaut II; c. 985 – 11 July 1004) was the eldest son and heir of Odo I, Count of Blois, and Bertha of Burgundy.
The stepson of Robert II of France, he became Count of Blois, Châteaudun, Chartres and Reims after the death of his father in 996.
Theobald II left no heirs; on his death, he was succeeded by his younger brother, Odo II, Count of Blois.
Theobald V, Count of Blois
Theobald V of Blois( 1130 – 20 January 1191), also known as Theobald the Good, was Count of Blois from 1151 to 1191.
Theobald VI, Count of Blois
Theobald VI of Blois( French:" Thibaut")( died 1218) was count of Blois and Clermont- en- Beauvaisis from 1205 to 1218.
He was son of Louis I of Blois and Catherine of Clermont.
Theobald married twice: with Maud of Alençon and with Clemence of Roches, but remained childless.
Clemence married Geoffrey VI, Viscount of Châteaudun, as her second husband.
Theobald fought the Moors in Castile.
During the campaign he contracted leprosy and returned home.
After living withdrawn in his castle in La Ferté- Villeneuil for a few years he died in 1218, leaving his possessions to his aunts Margaret and Isabelle.
The northern part of Blois was erected into the County of Chartres for Isabelle; Margaret received the remainder of the County of Blois, and he sold Clermont to the crown before he died.
Alix of France
Alix of France( July – August 1150 – 1197/1198) was countess consort of Blois by marriage to Theobald V, Count of Blois.
She was regent of Blois during the absence of her spouse in 1190- 1191, and regent during the minority of Louis I, Count of Blois from 1191 until 1197.

Question: What is the date of death of Joan, Countess Of Blois's mother?
Answer: 2 August 1288