Louis III, Count of Blois
Louis III of Châtillon( died 1372), son of Louis II, Count of Blois and Jeanne of Hainault, was count of Blois and lord of Avesnes 1346 – 1372, and count of Soissons 1346 – 1367.
After the Battle of Poitiers, he had to send his brother Guy as a hostage to London, and ultimately sold Soissons to Enguerrand VII de Coucy to ransom him.
Stephen I, Count of Troyes
Stephen I of Vermandois( died 1020) was the seventh Count of Meaux, in the Champagne region of modern -day France, after his father Herbert of Vermandois.
He died without issue.
The title of Count of Meaux passed to Odo II of Blois.
Maud of Normandy
Maud of Normandy( died 1006) was the daughter of Richard the Fearless and Gunnor.
Her siblings were Richard II" the Good", Duke of Normandy, Robert, Archbishop of Rouen, Count of Evreux, died 1037, Mauger, Count of Corbeil, Robert Danus, Emma of Normandy and Hawise of Normandy.
Maud was married to Odo II, Count of Blois but died young and without issue.
After her death in 1006, Odo started a quarrel with his brother- in- law, Richard II of Normandy, over the dowry: part of the town of Dreux.
King Robert II, who had married Odo's mother, imposed his arbitration on the contestants in 1007, leaving Odo in possession of Dreux.
Odo II, Count of Blois went on to marry Ermengarde, daughter of Robert I of Auvergne and have issue.
Bertha of Burgundy
Bertha of Burgundy (964 – 16 January 1010) was the daughter of Conrad the Peaceful, King of Burgundy and his wife Matilda, daughter of Louis IV, King of France and Gerberga of Saxony.
She was named for her father's mother, Bertha of Swabia.
She first married Odo I, Count of Blois in about 983.
They had several children, including Odo II.
After the death of her husband in 996, Bertha's second cousin Robert, co-King of France wished to marry her, in place of his repudiated first wife Rozala, who was many years his senior.
The union was opposed by Robert's father, Hugh Capet, due to the potential political problem that could be caused by religious authorities due to their consanguinity.
However, the marriage went ahead after Hugh's death in October 996, which left Robert as sole king.
The closeness of Robert and Bertha by blood was such that Church authorities considered the marriage illegal since they had not received a dispensation, nor had they requested one.
Accordingly, Pope Gregory V declared the pair excommunicated.
This, and the lack of children (save one, who lived and died in 999), caused Robert to agree with Pope Silvester II to have the marriage annulled in 1000.
Robert next married Constance of Arles while Bertha may have been the Bertha who married Arduin of Ivrea ("Arduino d´Ivrea"), King of Italy, Marquis of Ivrea.
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.
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.
Odo II, Count of Blois
Odo II  (983 – 15 November 1037) was the Count of Blois, Chartres, Châteaudun, Beauvais and Tours from 1004 and Count of Troyes (as Odo IV) and Meaux (as Odo I) from 1022.
He twice tried to make himself a king: first in Italy after 1024 and then in Burgundy after 1032.
Odo II was the son of Odo I of Blois and Bertha of Burgundy.
He was the first to unite Blois and Champagne under one authority although his career was spent in endless feudal warfare with his neighbors and suzerains, many of whose territories he tried to annex.
About 1003/4
he married Maud, a daughter of Richard I of Normandy.
After her death in 1005, and as she had no children, Richard II of Normandy demanded a return of her dowry: half the county of Dreux.
Odo refused and the two warred over the matter.
Finally, King Robert II, who had married Odo's mother, imposed his arbitration on the contestants in 1007, leaving Odo in possession of the castle Dreux while Richard II kept the remainder of the lands.
Odo quickly married a second wife, Ermengarde, daughter of .
Defeated by Fulk III, Count of Anjou, and Herbert I, Count of Maine, at the Battle of Pontlevoy in July 1016, he quickly tried to overrun the Touraine.
After the death of his cousin Stephen I in 1019/20, without heirs he seized Troyes, Meaux and all of Champagne for himself without royal approval.
From there he attacked Ebles, the archbishop of Reims, and Theodoric I, Duke of Lorraine.
Due to an alliance between the king and the Emperor Henry II he was forced to relinquish the county of Rheims to the archbishop.
He was offered the crown of Italy by the Lombard barons, but the offer was quickly retracted in order not to upset relations with the king of France.
In 1032, he invaded the Kingdom of Burgundy on the death of Rudolph III.
He retreated in the face of a coalition of the Emperor Conrad II and the new king of France, Henry I.
He died in combat near Bar-le-Duc during another attack on Lorraine.
Bertha of Blois
Bertha of Blois (French: "Berthe de Blois"; c. 1005 — c. 1080), was a Duchess consort of Brittany and a countess consort of Maine, married in 1018 to Alain III, Duke of Brittany, and in 1046 to Hugh IV, Count of Maine.
She was the daughter of Odo II, Count of Blois and Ermengarde of Auvergne.
Odo II, Viscount of Porhoët
Odo II, Count of Porhoet( died after 1180) was the son of Geoffroy, Viscount de Porhoët, and his wife Hawise( possibly Fergant).
He became Duke of Brittany in 1148 upon his marriage to Bertha, Duchess of Brittany.
On Bertha's death, Odo II denied her son Conan IV of Penthièvre, Duke of Brittany his inheritance.
While Odo II's marriage to Bertha was his first, it was her second marriage, her first being to Alain'le Noir' de Penthièvre, Lord of Richmond( Alan, 1st Earl of Richmond).
Odo II allied with his brother- in- law, Hoèl, Count of Nantes.
Odo II was deposed by his stepson Conan IV in 1156, and taken prisoner by Conan IV's ally Raoul de Fougères.
He married secondly, in 1167, to Alienor of Leon, daughter of Guihomar IV, Viscount of Léon and his wife Nobilis.
Children:( with Bertha) Children:( with Alienor of Léon) Possible child( with Joan/ Eleanor)
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.

Question: What is the date of death of Odo Ii, Count Of Blois's mother?
Answer: 16 January 1010