Christian of Oliva
Christian of Oliva, also Christian of Prussia( died 4 December 1245) was the first missionary bishop of Prussia.
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).
Prince Welf Henry of Hanover
Prince Welf Henry of Hanover(" Welf Heinrich Ernst August Georg Christian Berthold Friedrich Wilhelm Louis Ferdinand Prinz von Hannover"; 11 March 1923 – 12 July 1997) was the fourth son of Ernest Augustus, Duke of Brunswick and his wife Princess Victoria Louise of Prussia, the only daughter of Wilhelm II, German Emperor and Augusta Viktoria of Schleswig- Holstein.
The prince was known to his family as" Welfi."
Prince Albert of Prussia (1809–1872)
Prince Frederick Henry Albert of Prussia (4 October 1809 – 14 October 1872) was the fifth son and youngest child of King Frederick William III of Prussia and Louise of Mecklenburg-Strelitz.
His parents had fled to East Prussia after the occupation of Berlin by Napoleon, and Albert was born in Königsberg.
Two of Albert's elder brothers were Frederick William IV, King of Prussia from 1840 till 1861, and William I, King of Prussia from 1861 to 1888 and German Emperor from 1871 until 1888.
Princess Viktoria of Prussia
Princess Viktoria of Prussia (Friederike Amalia Wilhelmine Viktoria)
(12 April 1866 – 13 November 1929) was the second daughter of Frederick III, German Emperor and his wife Victoria, Princess Royal, a daughter of Queen Victoria.
To the public she was always Princess Viktoria, and in the family she was called "Moretta" or "Young Vicky".
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.
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.
Victoria, Princess Royal
Victoria, Princess Royal
(Victoria Adelaide Mary Louisa; 21 November 1840 – 5 August 1901) was German Empress and Queen of Prussia by marriage to German Emperor Frederick III.
She was the eldest child of Queen Victoria of the United Kingdom and Prince Albert of Saxe-Coburg and Gotha, and was created Princess Royal in 1841.
She was the mother of Wilhelm II, German Emperor.
Educated by her father in a politically liberal environment, Victoria was betrothed at the age of sixteen to Prince Frederick of Prussia and supported him in his views that Prussia and the later German Empire should become a constitutional monarchy on the British model.
Criticised for this attitude and for her English origins, Victoria suffered ostracism by the Hohenzollerns and the Berlin court.
This isolation increased after the rise to power of Otto von Bismarck (one of her most staunch political opponents) in 1862.
Victoria was empress for only a few months, during which she had opportunity to influence the policy of the German Empire.
Frederick III died in 1888 – just 99 days after his accession – from laryngeal cancer and was succeeded by their son William II, who had much more conservative views than his parents.
After her husband's death, she became widely known as Empress Frederick (German: "Kaiserin Friedrich").
The empress dowager then settled in Kronberg im Taunus, where she built Friedrichshof, a castle, named in honour of her late husband.
Increasingly isolated after the weddings of her younger daughters, Victoria died of breast cancer on 5 August 1901, not long after her mother's death on 22 January 1901.
The correspondence between Victoria and her parents has been preserved almost completely: 3,777 letters from Queen Victoria to her eldest daughter, and about 4,000 letters from the empress to her mother are preserved and catalogued.
These give a detailed insight into the life of the Prussian court between 1858 and 1900.
Prince Eitel Friedrich of Prussia
Prince Wilhelm Eitel Friedrich Christian Karl of Prussia (7 July 1883 – 8 December 1942) was the second son of Emperor Wilhelm II of Germany by his first wife, Augusta Viktoria of Schleswig-Holstein.
He was born and died in Potsdam, Germany.
Prince Christian Oscar of Hanover
Prince Christian Oscar of Hanover (1 September 1919 – 10 December 1981) was the fourth child of Ernest Augustus, Duke of Brunswick and his wife Princess Victoria Louise of Prussia, the only daughter of Wilhelm II, German Emperor and Augusta Viktoria of Schleswig-Holstein.

Question: Why did Princess Viktoria Of Prussia's mother die?
Answer: breast cancer