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.
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.
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.
Isolde Beidler
Isolde Beidler (born Isolde von Bülow: 10 April 1865 – 7 February 1919) was the third of the five stepchildren and children of the composer Richard Wagner and his wife, who is generally known as Cosima Wagner (though the two of them married only in 1870).
Isolde herself married the Swiss-born conductor (1872-1930) and was the mother of author (1901-1981), celebrated at his birth as "Richard Wagner's first grandchild".
In view of the enduring interest in Richard Wagner's antisemitic opinions, it becomes intriguing that in 1923 Isolde Beidler posthumously acquired a Jewish daughter-in-law.
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.
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.
Hannah Arnold
Hannah Arnold, also known as Hannah Waterman King, was the grandmother of Benedict Arnolds children.
Gülbahar Hatun (wife of Mehmed II)
Gülbahar Hatun( 1432 – 1492) was the consort of Sultan Mehmed II, and mother of Sultan Bayezid II of the Ottoman Empire and the grandmother of Selim I.
Hüma Hatun
Hüma Hatun (1410 ‒ September 1449) was the fourth wife of Ottoman Sultan Murad II and mother of Mehmed II and the grandmother of Bayezid II.
Cosima Wagner
Cosima Wagner (born Francesca Gaetana Cosima Liszt; 24 December 1837 – 1 April 1930) was the illegitimate daughter of the Hungarian pianist and composer Franz Liszt and Marie d'Agoult.
She became the second wife of the German composer Richard Wagner, and with him founded the Bayreuth Festival as a showcase for his stage works; after his death she devoted the rest of her life to the promotion of his music and philosophy.
Commentators have recognised Cosima as the principal inspiration for Wagner's later works, particularly "Parsifal".
In 1857, after a childhood largely spent under the care of her grandmother and with governesses, Cosima married the conductor Hans von Bülow.
Although the marriage produced two children, it was largely a loveless union, and in 1863 Cosima began a relationship with Wagner, who was 24 years her senior.
She married him in 1870; after his death in 1883 she directed the Bayreuth Festival for more than 20 years, increasing its repertoire to form the Bayreuth canon of ten operas and establishing the festival as a major event in the world of musical theatre.
During her directorship, Cosima opposed theatrical innovations and adhered closely to Wagner's original productions of his works, an approach continued by her successors long after her retirement in 1907.
She shared Wagner's convictions of German cultural and racial superiority, and under her influence, Bayreuth became increasingly identified with antisemitism.
This was a defining aspect of Bayreuth for decades, into the Nazi era which closely followed her death in 1930.
Thus, although she is widely perceived as the saviour of the festival, her legacy remains controversial.

Question: Who is Isolde Beidler's maternal grandmother?
Answer: Marie d'Agoult