Maria of Brabant, Duchess of Bavaria
Maria of Brabant( 1226–1256) was a daughter of Henry II, Duke of Brabant, and Maria of Swabia.
She married Louis II, Duke of Bavaria, being the first of three wives.
Margaret of Foix
Margaret of Foix( French:" Marguerite de Foix"; c. 1449 – 15 May 1487) was Duchess of Brittany from 1474 to 1486 by marriage to Francis II, Duke of Brittany.
Hoël II, Duke of Brittany
Hoël II (c. 1031–1084) was Count of Kernev ("French: CornouailleBreton: Kernev"), from 1058 as Hoël V.
On the basis of his marriage to Hawise, Duchess of Brittany, in 1066, he became Duke of Brittany "jure uxoris".
Hoël was the son of Alan of Cornwall and his wife, Judith of Nantes, granddaughter of the illegitimate son of Alan II of Brittany.
Hoël started the House of Kernev (Cornouaille) of Brittany, which ruled the Duchy until 1156.
Little is known of the lives of Hawise and Hoël.
However, this political marriage between the House of Rennes in the east and the House of Cornouaille in the west may have further strengthened Brittany at a time when external interference was attempted by William the Conqueror.
After Hawise's death in 1072, Hoël acted as regent for his son, Alan IV, until the latter reached his majority in 1084.
During his reign he faced several rebellions from Breton nobles.
Geoffrey Grenonat of Rennes (a natural son of Duke Alan III of Brittany and thus a half-brother of Hawise) led a revolt and was joined by Ralph de Gael who had returned to Brittany from England after the failure of the previous year's Revolt of the Earls.
In 1076, Ralph having plotted against Hoël, was besieged at Dol.
William the Conqueror came to Hoël's aid, after which Hoël finally made peace with Ralph.
Hoël's second son, Matthew, succeeded to the county of Nantes.
Hawise, Duchess of Brittany
Hawise of Rennes  (1037 – 19 August 1072) was sovereign Duchess of Brittany from 1066 until her death.
She was the second child and heiress of Alan III, Duke of Brittany, by his wife, Bertha of Blois, and as such, a member of the House of Rennes.
Hawise succeeded her older brother, Conan II, who was assassinated by poisoning on 11 December 1066.
Little is known of the life of Hawise of Rennes.
She was married to Hoel of Cornwall some time before 1058.
Hoel exercised authority "jure uxoris" and continued to control the government after her death in 1072 acting as regent for their son, Alan IV.
A second son, Matthew, inherited the county of Nantes.
Alain Canhiart
Alain Canhiart( died 1058) was the Count of Cornouaille from 1020- 1058.
He was the son of Benoît de Cornouaille and the father of Hoel II, Duke of Brittany.
His family name," Canhiart", is understood to be derived from the old Breton Kann Yac'h and was translated into the Latin texts of his era as" Bellator fortis".
Marie of Brittany, Countess of Saint-Pol
Marie of Brittany( 1268–1339) was the daughter of John II, Duke of Brittany, and Beatrice of England.
She is also known as Marie de Dreux.
Blanche of Brittany
Blanche of Brittany( 1271 – 1327) was a daughter of John II, Duke of Brittany, and his wife Beatrice of England.
She is also known as Blanche de Dreux.
Through her mother she was the granddaughter of King Henry III of England and Eleanor of Provence.
Ogawa Mataji
Viscount was a general in the early Imperial Japanese Army.
He was also the father- in- law of Field Marshal Gen Sugiyama.
Alan IV, Duke of Brittany
Alan IV( born circa 1063; died 13 October 1119) was Duke of Brittany from 1084 until his abdication in 1112.
He was also Count of Nantes( from c. 1103) and Count of Rennes.
His parents were Duchess Hawise and Duke Hoel II.
He is also known as Alan Fergant.
Through his father, he was of the Breton House of Cornouaille dynasty( Breton:" Kerne" dynasty).
He was the last Breton- speaking Duke of Brittany.
Odo, Count of Penthièvre
Odo of Rennes( Medieval Breton:" Eudon Pentevr", Modern Breton:" Eozen Penteur", Latin:" Eudo", French:" Eudes/ Éon de Penthièvre")( 999–1079), Count of Penthièvre, was the youngest of the three sons of Duke Geoffrey I of Brittany and Hawise of Normandy, daughter of Richard I of Normandy.
Eozen married Agnes of Cornouaille( Orguen Kernev), the daughter of Alan Canhiart, Count of Cornouaille and sister of Hoel II, Duke of Brittany who was married in 1066 to Eozen's niece Hawise, Duchess of Brittany.

Question: Who is the father-in-law of Hoël Ii, Duke Of Brittany?
Answer: Alan III, Duke of Brittany