Lady Brigid Guinness
Lady Brigid Katharine Rachel Guinness( 30 July 19208 March 1995) was the youngest daughter of Rupert Guinness, 2nd Earl of Iveagh, and wife of Prince Frederick of Prussia, grandson of Wilhelm II, German Emperor.
Prince Frederick of Prussia (1911–1966)
Prince Frederick of Prussia (19 December 1911 – 20 April 1966), also known as "Mr. Friedrich von Preussen" in the United Kingdom, was the fourth son of Crown Prince Wilhelm of Germany and Duchess Cecilie of Mecklenburg-Schwerin.
Prince William of Hesse-Kassel
Prince William of Hesse- Kassel( 24 December 1787 – 5 September 1867), was the first son of Prince Frederick of Hesse- Kassel and Princess Caroline of Nassau- Usingen.
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 Marie of Prussia (1855–1888)
Princess Marie of Prussia(" Marie Elisabeth Louise Frederika"; 14 September 1855, Marmorpalais, Potsdam – 20 June 1888, Dresden), was a princess of the House of Hohenzollern.
She was the daughter of Prince Frederick Charles of Prussia and later became second wife of Prince Henry of the Netherlands then the first wife of Prince Albert of Saxe- Altenburg.
She was also the great- niece of Wilhelm I, German Emperor.
Prince Frederick Adolf, Duke of Östergötland
Prince Frederick Adolf of Sweden( 18 July 1750 in Drottningholm – 12 December 1803 in Montpellier, France) was a Swedish Prince, youngest son of King Adolf Frederick of Sweden and Louisa Ulrika of Prussia, a sister of Frederick the Great, King of Prussia.
He was given the title Duke of Östergötland.
Prince Frederick of the Netherlands
Prince Frederick of the Netherlands, Prince of Orange- Nassau( full names: Willem Frederik Karel; 28 February 1797 in Berlin – 8 September 1881 in Wassenaar), was the second son of William I of the Netherlands and his wife, Wilhelmine of Prussia.
Princess Frederica Charlotte of Prussia
Princess Frederica Charlotte of Prussia
( Friederike Charlotte Ulrike Katharina; 7 May 1767 – 6 August 1820) was a Prussian and British princess.
She was the eldest daughter of King Frederick William II of Prussia and the wife of Prince Frederick, Duke of York and Albany, second son of King George III of the United Kingdom.
Prince Alexander of Prussia
Prince Friedrich Wilhelm Ludwig" Alexander" of Prussia( 21 June 1820 – 4 January 1896) was the eldest child of Prince Frederick of Prussia and his wife, Princess Luise of Anhalt- Bernburg.
Duchess Cecilie of Mecklenburg-Schwerin
Duchess Cecilie of Mecklenburg-Schwerin (Cecilie Auguste Marie; 20 September 1886 – 6 May 1954) was the last German Crown Princess and Crown Princess of Prussia as the wife of German Crown Prince Wilhelm, the son of German Emperor Wilhelm II.
Cecilie was a daughter of Frederick Francis III, Grand Duke of Mecklenburg-Schwerin and Grand Duchess Anastasia Mikhailovna of Russia.
She was brought up with simplicity and her early life was peripatetic, spending summers in Mecklenburg and the rest of the year in the south of France.
After the death of her father, she traveled every summer between 1898 and 1904 to her mother's native Russia.
On 6 June 1905, she married German Crown Prince Wilhelm.
The couple had four sons and two daughters.
Cecile, tall and statuesque, became popular in Germany for her sense of style.
However, her husband was a womanizer and the marriage was unhappy.
After the fall of the German monarchy, at the end of World War I, Cecile and her husband lived mostly apart.
During the Weimar Republic and the Nazi period, Cecilie lived a private life mainly at Cecilienhof Palace in Potsdam.
With the advance of the Soviet troops, she left the Cecilienhof in February 1945, never to return.
She settled in Bad Kissingen until 1952 when she moved to an apartment in the Frauenkopf district of Stuttgart.
In 1952, she published a book of memoirs.
She died two years later.

Question: Where did Prince Frederick Of Prussia (1911–1966)'s mother die?
Answer: Kissingen