Sophie, Princess of Prussia
Sophie Johanna Maria, Princess of Prussia( née" Princess of Isenburg", born 7 March 1978) is the wife of Georg Friedrich, Prince of Prussia, head of the House of Hohenzollern, members of which reigned as kings of Prussia and as German emperors until deposed in 1918.
Princess Charlotte of Prussia (1831–1855)
Princess Charlotte of Prussia( 21 June 1831 – 30 March 1855), was by birth a Princess of Prussia and member of the House of Hohenzollern and by marriage Hereditary Princess of Saxe- Meiningen.
She was the eldest child and daughter of Prince Albert of Prussia( younger son of Frederick William III of Prussia and Louise of Mecklenburg- Strelitz) and his first wife Princess Marianne of the Netherlands( daughter of William I of the Netherlands and Wilhelmine of Prussia).
Princess Calixta of Lippe
Princess "Calixta" Agnes Adelaide Irmgard Helene Caroline Elise Emma of Lippe (14 October 1895 - 15 December 1982) was the wife of Prince Waldemar of Prussia, eldest son of Prince Henry of Prussia.
Waldemar of Sweden (disambiguation)
Waldemar of Sweden- Swedish:" Valdemar"- may refer to:
Princess Elisabeth of Prussia
Princess Elisabeth of Prussia( 18 June 1815 – 21 March 1885) was the second daughter of Prince Wilhelm of Prussia and Landgravine Marie Anna of Hesse- Homburg and a granddaughter of Frederick William II of Prussia.
Prince Philip, Duke of Edinburgh is her great- great- grandson.
Christian of Oliva
Christian of Oliva, also Christian of Prussia( died 4 December 1245) was the first missionary bishop of Prussia.
Prince Waldemar of Prussia (1868–1879)
Prince Joachim Friedrich Ernst Waldemar of Prussia (10 February 1868 – 27 March 1879) was the sixth child and youngest son of Crown Prince Friedrich (later Emperor Friedrich III), and Victoria, Princess Royal, the eldest daughter of the Queen Victoria.
Prince Waldemar of Prussia (1889–1945)
Prince Waldemar William Louis Frederick Victor of Prussia( 20 March 1889 at Kiel – 2 May 1945 at Tutzing, Bavaria) was the eldest son of Prince Henry of Prussia and his wife, Princess Irene of Hesse and by Rhine.
Princess Eleonore of Schaumburg-Lippe
Princess Eleonore- Christine of Schaumburg- Lippe( Eleonore- Christine Eugenie Benita Feodora Maria; born 22 December 1978 at Hørsholm, Denmark) is the daughter of Prince Waldemar of Schaumburg- Lippe and his first wife, Anne- Lise Johansen.
Princess Eleonore- Christine is a great- great- granddaughter of King Frederick VIII of Denmark.
He is in the line of succession to the British throne as a descendant of George II of the United Kingdom's daughter Queen Caroline Matilda of Denmark and Norway.
Frederick III, German Emperor
Frederick III (18 October 1831 – 15 June 1888) was German Emperor and King of Prussia for ninety-nine days in 1888, the Year of the Three Emperors.
Known informally as "Fritz", he was the only son of Emperor Wilhelm I and was raised in his family's tradition of military service.
Although celebrated as a young man for his leadership and successes during the Second Schleswig, Austro-Prussian and Franco-Prussian wars, he nevertheless professed a hatred of warfare and was praised by friends and enemies alike for his humane conduct.
Following the unification of Germany in 1871 his father, then King of Prussia, became the German Emperor.
Upon Wilhelm's death at the age of ninety on 9 March 1888, the thrones passed to Frederick, who had by then been German Crown Prince for seventeen years and Crown Prince of Prussia for twenty-seven years.
Frederick was suffering from cancer of the larynx when he died, aged fifty-six, following unsuccessful medical treatments for his condition.
Frederick married Victoria, Princess Royal, eldest daughter of Queen Victoria of the United Kingdom.
The couple were well-matched; their shared liberal ideology led them to seek greater representation for commoners in the government.
Frederick, in spite of his conservative militaristic family background, had developed liberal tendencies as a result of his ties with Britain and his studies at the University of Bonn.
As the Crown Prince, he often opposed the conservative Chancellor Otto von Bismarck, particularly in speaking out against Bismarck's policy of uniting Germany through force, and in urging that the power of the Chancellorship be curbed.
Liberals in both Germany and Britain hoped that as emperor, Frederick III would move to liberalize the German Empire.
Frederick and Victoria were great admirers of Prince Albert, Queen Victoria's husband.
They planned to rule as consorts, like Albert and Queen Victoria, and to reform what they saw as flaws in the executive branch that Bismarck had created for himself.
The office of Chancellor, responsible to the Emperor, would be replaced with a British-style cabinet, with ministers responsible to the Reichstag.
Government policy would be based on the consensus of the cabinet.
Frederick "described the Imperial Constitution as "ingeniously contrived chaos.
According to Michael Balfour:
However, Frederick's illness prevented him from effectively establishing policies and measures to achieve this, and such moves as he was able to make were later abandoned by his son and successor, Wilhelm II.
The timing of Frederick's death and the length of his reign are important topics among historians.
His premature demise is considered a potential turning point in German history; and whether or not he would have made the Empire more liberal if he had lived longer is still discussed.

Question: What is the cause of death of Prince Waldemar Of Prussia (1868–1879)'s father?
Answer: cancer of the larynx