Hannah Arnold
Hannah Arnold, also known as Hannah Waterman King, was the grandmother of Benedict Arnolds children.
Anne Denman
Anne Denman( 1587–1661) was born in Olde Hall, Retford, Nottinghamshire.
Through a fortunate second marriage with Thomas Aylesbury, she became the grandmother of Lady Anne Hyde, Duchess of York and great- grandmother of Queen Mary II and Queen Anne.
Purnima (Hindi actress)
Purnima Das Verma( born Meherbhano Mohammad Ali) was an Indian film actress who worked predominantly in Hindi language films.
She is the grandmother of actor Emraan Hashmi.
Tjuyu
Tjuyu( sometimes transliterated as Thuya or Thuyu) was an Egyptian noblewoman and the mother of queen Tiye, and the wife of Yuya.
She is the grandmother of Akhenaten, and great grandmother of Tutankhamun.
Kaoru Hatoyama
After the elections of 2009, she became more widely known as the grandmother of Prime Minister Yukio Hatoyama and his politician brother Kunio Hatoyama.
Mona Hopton Bell
Mona Hopton Bell( 1867- 1940) was a British artist, best known for her portraits of civic figures.
She was the grandmother of the painter Jean H. Bell.
Grimoald the Younger
Grimoald II  (died 714), called the Younger, was the mayor of the palace of Neustria from 695.
He was the second son of Pepin of Herstal and Plectrude and his father placed him in the office of mayor of the palace in the Neustrian kingdom in 695, when he was still young.
He married Theudesinda (or Theodelinda), daughter of Radbod, King of the Frisians, and had two sons: Theudoald and Arnold.
While en route to visit the tomb of Saint Lambert at Liège, he was assassinated by a certain Rangar, in the employ of his father-in-law.
His sons carried on a fight to be recognised as Pepin of Herstal's true heirs, since Grimoald predeceased his father and his half-brother Charles Martel usurped the lands and offices of their father.
In short, he was innocent but unlucky.
Hubba bint Hulail
Hubba bint Hulail was the grandmother of Hashim ibn' Abd Manaf, thus the great- great- great- grandmother of the Islamic" Nabī"( Prophet) Muhammad ibn Abdullah.
Diana Guardato
Diana Guardato was a member of the aristocratic Patrician Guardato family, and had three children with King Ferdinand I: Diana Guardato is the 16th- Great Grandmother of His Royal Highness Albert II of Belgium, 15th- Great Grandmother of His Majesty Juan Carlos
I of Spain, 17th- Great Grandmother of Philippe of Belgium, 14th- Great Grandmother of His Majesty Manuel II of Portugal, 16th- Great Grandmother of Grand Duke Henri, as well as many others.
Plectrude
Plectrude  (died 718) was the consort of Pepin of Herstal, the mayor of the palace and duke of the Franks, from about 670.
She was the daughter of Hugobert, seneschal of Clovis IV, and Irmina of Oeren.
She was the regent of Neustria during the minority of her grandson Theudoald from 714 until 718.

Question: Who is the maternal grandmother of Grimoald The Younger?
Answer: Irmina of Oeren