Georg, Prince of Schaumburg-Lippe
Georg, Prince of Schaumburg- Lippe( 10 October 1846 – 29 April 1911) was a ruler of the small Principality of Schaumburg- Lippe.
Prince Christian of Schaumburg-Lippe (1898–1974)
Prince Christian of Schaumburg-Lippe (20 February 1898 – 13 July 1974) was a German prince and head of the Náchod branch of the princely house of Schaumburg-Lippe.
He was born in Sopron, Hungary, the only son and second child of Frederick of Schaumburg-Lippe (1868–1945) and his first wife Princess Louise of Denmark, younger sister of King Christian X of Denmark.
Prince Waldemar of Schaumburg-Lippe
Prince Waldemar Stephen of Schaumburg- Lippe(" Waldemar Stephan Ferdinand Wolrad Friedrich Karl", b. 19 December 1940 in Glienicke) is a son of Prince Christian of Schaumburg- Lippe and Princess Feodora of Denmark, and the great- grandson of King Frederick VIII of Denmark.
Prince Frederick of Schaumburg-Lippe
Prince Frederick of Schaumburg- Lippe( 30 January 186812 December 1945) was a German prince and head of the Náchod branch of the princely house of Schaumburg- Lippe.
He was a son of Prince William of Schaumburg- Lippe, by his wife Princess Bathildis of Anhalt- Dessau.
Heinrich Donatus, Hereditary Prince of Schaumburg-Lippe
Heinrich Donatus, Hereditary Prince of Schaumburg- Lippe( Ernst- August Alexander Wilhelm Bernhard Krafft Heinrich Donatus; born 13 May 1994) is the son of Alexander, Prince of Schaumburg- Lippe and thus heir to the German Princely house of Schaumburg- Lippe.
Prince Heinrich Donatus of Schaumburg- Lippe was born in Hanover to Alexander, Hereditary Prince of Schaumburg- Lippe( born 1958), and Princess Marie- Louise(" Lilly") of Sayn- Wittgenstein- Berleburg( born 1972), who had married in August 1993.
His mother suffered a nervous breakdown in 1998, and left her husband in 2000 to move with her son from Hanover to Munich.
The couple divorced in 2002.
On the death of his father, Philip- Ernst, Prince of Schaumburg- Lippe, Alexander inherited the title Prince of Schaumburg- Lippe, while his son became Hereditary Prince.
In 2007, the Prince of Schaumburg- Lippe married lawyer Nadja Anna Zsoeks.
Princess Marie- Louise is now married to designer Lambros Milona, with whom she has a daughter, Lana.
Princess Feodora of Denmark
Princess Feodora of Denmark( Feodora Louise Caroline- Mathilde Viktoria Alexandra Frederikke Johanne)
( 3 July 1910 – 17 March 1975) was a Danish princess as a daughter of Prince Harald of Denmark and granddaughter of Frederick VIII of Denmark.
As the wife of Prince Christian of Schaumburg- Lippe she became a Princess of Schaumburg- Lippe by marriage.
Princess Louise of Denmark (1875–1906)
Princess Louise of Denmark ("Louise Caroline Josephine Sophie Thyra Olga")
(17 February 1875 – 4 April 1906) was a Danish princess, the third child and oldest daughter of Frederick VIII of Denmark and his wife, Princess Louise of Sweden and Norway.
Adolf I, Prince of Schaumburg-Lippe
Adolf I, Prince of Schaumburg-Lippe (1 August 1817 – 8 May 1893) was a ruler of the Principality of Schaumburg-Lippe.
Adolf II, Prince of Schaumburg-Lippe
Adolf II, Prince of Schaumburg- Lippe( 23 February 1883 – 26 March 1936) was the last ruler of the small Principality of Schaumburg- Lippe.
Prince Wilhelm of Schaumburg-Lippe (b. 1939)
Prince Wilhelm of Schaumburg- Lippe( Wilhelm Friedrich Harald Christian Ernst August Karl Gustav zu Schaumburg- Lippe, born 19 August 1939) is the head of the Nachod branch of the princely house of Schaumburg- Lippe.
Wilhelm is the son of Prince Christian Nicholas of Schaumburg- Lippe, and the great- grandson of Frederick VIII of Denmark.

Question: Who is Prince Christian Of Schaumburg-Lippe (1898–1974)'s maternal grandfather?
Answer: Frederick VIII of Denmark