Princess Eugénie of Greece and Denmark
Princess Eugénie of Greece and Denmark( 10 February 1910 – 13 February 1989) was the youngest child and only daughter of Prince George of Greece and Denmark and his wife, Princess Marie Bonaparte, daughter of Marie- Félix Blanc and Prince Roland Bonaparte, a great- nephew of Napoleon I.
Her father was the second son of George I of Greece and Olga Constantinovna of Russia.
As a cousin of the bridegroom, she was a leading guest at the 1947 wedding of Princess Elizabeth and Philip, Duke of Edinburgh.
She authored" Le Tsarevitch, Enfant Martyr", a biography of Aleksey Nikolaevich, Tsarevich of Russia, written in French, which was published in 1990.
Princess Xenia Georgievna of Russia
Princess Xenia Georgievna of Russia( 22 August 1903, Mikhailovskoe, Russia – 17 September 1965, Glen Cove, New York) was the younger daughter of Grand Duke George Mihailovich of Russia and Princess Maria Georgievna of Greece and Denmark.
She was a granddaughter of George I of Greece and first cousin of the brothers King Alexander I of Greece, King George II of Greece, King Paul I of Greece and their sister Queen Helen, Queen Mother of Romania and also of Prince Philip, Duke of Edinburgh.
Princess Margarita of Greece and Denmark
Princess Margarita of Greece and Denmark( 18 April 1905 – 24 April 1981) was the eldest child and daughter of Prince Andrew of Greece and Denmark and Princess Alice of Battenberg.
She was the first great- great- grandchild of Queen Victoria, and the eldest sister of Prince Philip, Duke of Edinburgh.
Princess Anastasia of Greece and Denmark
Princess Anastasia of Greece and Denmark ("née" Nonie May Stewart; 20 January 1878 – 29 August 1923) was an American-born heiress and member of the Greek Royal Family.
She was married to Prince Christopher of Greece and Denmark, the youngest child of King George I of Greece and his consort, Grand Duchess Olga Constantinovna of Russia, but was created a princess "suo jure".
Princess Elizabeth of Greece and Denmark
Princess Elisabeth of Greece and Denmark( 24 May 1904 – 11 January 1955) was the middle daughter of Prince Nicholas of Greece and Grand Duchess Elena Vladimirovna of Russia.
Prince George of Greece and Denmark
Prince George of Greece and Denmark (Greek:
Πρίγκιπας Γεώργιος; 24 June 1869 – 25 November 1957) was the second son and child of George I of Greece and Olga Konstantinovna of Russia, and is remembered chiefly for having once saved the life of his cousin the future Emperor of Russia, Nicholas II in 1891 during their visit to Japan together.
He served as high commissioner of the Cretan State during its transition towards independence from Ottoman rule and union with Greece.
Princess Sophie of Greece and Denmark
Princess Sophie of Greece and Denmark( 26 June 1914 – 24 November 2001) was the fourth child and youngest daughter of Prince Andrew of Greece and Denmark and Princess Alice of Battenberg.
The Duke of Edinburgh is her younger brother.
Sophie was born at the villa Mon Repos on the island of Corfu in Greece.
Princess Theodora of Greece and Denmark (1906–1969)
Princess Theodora of Greece and Denmark( 30 May 1906 – 16 October 1969) was the second child and daughter of Prince Andrew of Greece and Denmark and Princess Alice of Battenberg, and the second eldest sister of Prince Philip, Duke of Edinburgh.
George I of Greece
George I (Greek:
Γεώργιος Α΄, Geórgios I; 24 December 1845 – 18 March 1913) was King of Greece from 1863 until his assassination in 1913.
Originally a Danish prince, he was born in Copenhagen, and seemed destined for a career in the Royal Danish Navy.
He was only 17 years old when he was elected king by the Greek National Assembly, which had deposed the unpopular former king Otto.
His nomination was both suggested and supported by the Great Powers: the United Kingdom of Great Britain and Ireland, the Second French Empire and the Russian Empire.
He married the Russian grand duchess Olga Constantinovna of Russia in 1867, and became the first monarch of a new Greek dynasty.
Two of his sisters, Alexandra and Dagmar, married into the British and Russian royal families.
King Edward VII and Tsar Alexander III were his brothers-in-law, and King George V, Tsar Nicholas II, King Christian X of Denmark and King Haakon VII of Norway were his nephews.
George's reign of almost 50 years (the longest in modern Greek history) was characterized by territorial gains as Greece established its place in pre-World War
I Europe.
Britain ceded the Ionian Islands peacefully in 1864, while Thessaly was annexed from the Ottoman Empire after the Russo-Turkish War (1877–1878).
Greece was not always successful in its territorial ambitions; it was defeated in the Greco-Turkish War (1897).
During the First Balkan War, after Greek troops had captured much of Greek Macedonia, George was assassinated in Thessaloniki.
Compared with his own long tenure, the reigns of his successors Constantine, Alexander, and George II proved short and insecure.
Princess Olga of Greece and Denmark
Princess Olga of Greece and Denmark( Serbian Cyrillic:" Кнегиња Олга Карађорђевић"; 11 June 1903 – 16 October 1997) was a granddaughter of King George I of Greece and wife of Prince Paul, Regent of the Kingdom of Yugoslavia.

Question: Who is Prince George Of Greece And Denmark's mother?
Answer: Olga Constantinovna of Russia