Ethel Kennedy
Ethel Skakel Kennedy (born April 11, 1928) is an American human rights advocate.
Kennedy is the widow of U.S. Senator Robert F. Kennedy as well as the sixth child of George Skakel and Ann Brannack.
She married Robert F. Kennedy in 1950, and the couple had eleven children together.
Shortly after her husband's June 5, 1968 assassination, Kennedy founded the Robert F. Kennedy Center for Justice and Human Rights.
The organization is a nonprofit charity working to realize Robert F. Kennedy's dream of a just and peaceful world.
In 2014, Ethel Kennedy was awarded the Presidential Medal of Freedom by President Barack Obama.
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.
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.
Douglas Harriman Kennedy
Douglas Harriman Kennedy (born March 24, 1967) is an American journalist.
He is the tenth child of Robert F. Kennedy and Ethel Kennedy, named in honor of W. Averell Harriman, a family friend and former governor of New York.
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.
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.
Archibald I, Lord of Douglas
Archibald of Douglas( before 1198 – d.c. 1238) was a Scottish Nobleman.
He was the son of William of Douglas.
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.

Question: Who is Douglas Harriman Kennedy's maternal grandmother?
Answer: Ann Brannack