Princess Thyra of Denmark
Princess Thyra of Denmark,,( 29 September 1853 – 26 February 1933, in Gmunden) was the youngest daughter and fifth child of Christian IX of Denmark and Louise of Hesse- Kassel.
In 1878, she married Ernest Augustus, the exiled heir to the Kingdom of Hanover.
As the Kingdom of Hanover had been annexed by Prussia in 1866, she spent most of her life in exile with her husband in Austria.
Thyra was the younger sister of Frederik VIII of Denmark, Queen Alexandra of the United Kingdom, George I of Greece, Empress Maria Feodorovna of Russia and an elder sister of Prince Valdemar of Denmark.
Princess Thyra of Denmark (1880–1945)
Princess Thyra of Denmark and Iceland (Thyra Louise Caroline
Amalie Augusta Elisabeth; Copenhagen, 14 March 1880 – Copenhagen, 2 November 1945) was the sixth child and third daughter of Frederick VIII of Denmark and his wife, Princess Louise of Sweden and Norway.
She was named for her paternal aunt, Princess Thyra of Denmark.
She died unmarried and without issue.
Princess Caroline-Mathilde of Denmark
Princess Caroline- Mathilde of Denmark( 27 April 1912 – 12 December 1995) was a daughter of Prince Harald of Denmark and granddaughter of King Frederick VIII of Denmark.
As the wife of Knud, Hereditary Prince of Denmark, she became Hereditary Princess of Denmark.
Prince George William of Hanover (1880–1912)
George William, Hereditary Prince of Hanover(" Georg Wilhelm Christian Albert Edward Alexander Friedrich Waldemar Ernst Adolf Prinz von Hannover"; 28 October 1880 – 20 May 1912) was the eldest son of Ernest Augustus, Crown Prince of Hanover( 1845 – 1923) and Princess Thyra of Denmark( 1853 – 1933), the youngest daughter of Christian IX of Denmark( 1818–1906) and Louise of Hesse- Kassel( 1817–1898).
George William was a great- great- grandson of George III of the United Kingdom( 1738 – 1820) and Charlotte of Mecklenburg- Strelitz( 1744 – 1818).
Louise of Sweden
Louise of Sweden (Louise Josephine Eugenie ; 31 October 1851 – 20 March 1926), was Queen of Denmark as the spouse of King Frederick VIII.
She was the only surviving child of Charles XV of Sweden and his consort, Louise of the Netherlands.
She was the mother of both King Christian X of Denmark and King Haakon VII of Norway.
Prince Christian of Hanover (1885–1901)
Prince Christian of Hanover(" Christian Friedrich Wilhelm Georg Peter Waldemar Prinz von Hannover"; 4 July 1885 – 3 September 1901) was the second eldest son of Ernest Augustus, Crown Prince of Hanover( 1845 – 1923) and Princess Thyra of Denmark( 1853 – 1933), the youngest daughter of Christian IX of Denmark( 1818–1906) and Louise of Hesse- Kassel( 1817–1898).
Christian was a great- great- grandson of George III of the United Kingdom( 1738 – 1820) and Charlotte of Mecklenburg- Strelitz( 1744 – 1818).
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.
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.
Princess Marie Louise of Hanover
Princess Marie Louise of Hanover and Cumberland( 11 October 1879 – 31 January 1948) was the eldest child of Ernest Augustus, Crown Prince of Hanover, and Princess Thyra of Denmark, the youngest daughter of Christian IX of Denmark and Louise of Hesse- Kassel.
Through her father, Marie Louise was a great- great- granddaughter of George III of the United Kingdom and Charlotte of Mecklenburg- Strelitz.
She was a first cousin of Nicholas II of Russia and George V of the United Kingdom.

Question: Who is Princess Thyra Of Denmark (1880–1945)'s maternal grandmother?
Answer: Louise of the Netherlands