Who was the granddaughter of Queen Victoria of the United Kingdom who also has a grandson that was the first descendant of all three of Victoria, Duchess of Kent's children?
Emich Kyrill, Prince of Leiningen: Emich was born at Coburg, Weimar Republic, the first child of Karl, Prince of Leiningen (1898–1946), (son of Emich, 5th Prince of Leiningen and Princess Feodore of Hohenlohe-Langenburg) and his wife, Grand Duchess Maria Kirillovna of Russia (1907–1951), (daughter of Cyril Vladimirovich, Grand Duke of Russia and Princess Victoria Melita of Saxe-Coburg and Gotha). Emich Kyrill, Prince of Leiningen:  As a result, Emich was the first descendant of all three of Victoria, Duchess of Kent's children. Princess Victoria Melita of Saxe-Coburg and Gotha:  She was a granddaughter of Queen Victoria of the United Kingdom and Emperor Alexander II of Russia.
Princess Victoria Melita of Saxe-Coburg and Gotha