Princess Elena of Romania
Princess Elena of Romania (born 15 November 1950) is the second daughter of King Michael I and Queen Anne of Romania.
She is currently first in the line of succession to the former Romanian throne and headship of the House of Romania as her elder sister Margareta has no issue.
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.
Nicholas Medforth-Mills
Nicholas Michael de Roumanie Medforth-Mills, formerly Prince Nicholas of Romania, (born 1 April 1985) is the eldest child and only son of Princess Elena of Romania and Robin Medforth-Mills.
As a grandson of Michael I, the former king of Romania, he was third in line to the defunct throne of Romania according to a new family statute enacted in 2007, that also conferred the title of a "prince of Romania" on him which was abrogated in 2015.
The statute and the titles it confers have no standing in present Romanian law.
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.
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.
Robin Medforth-Mills
Leslie Robin Medforth-Mills (8 December 1942 – 2 February 2002) was a British professor of geography at the University of Durham and a United Nations official.
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.
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.
Hannah Arnold
Hannah Arnold, also known as Hannah Waterman King, was the grandmother of Benedict Arnolds children.
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.

Question: Who is Nicholas Medforth-Mills's maternal grandmother?