Princess Marie-Cécile of Prussia, is the daughter of Louis Ferdinand, Prince of Prussia, and his wife, Grand Duchess Kira Kirillovna of Russia, maternally, she is a granddaughter of who was later titled, Grand Duchess Victoria Feodorovna of Russia, who is the he third child and second daughter of Alfred, Duke of Saxe-Coburg and Gotha?
Princess Marie Cécile of Prussia:  Her paternal grandparents were William, German Crown Prince, and Duchess Cecilie of Mecklenburg-Schwerin; maternally, she is a granddaughter of Cyril Vladimirovich, Grand Duke of Russia, and Princess Victoria Melita of Saxe-Coburg and Gotha. Princess Victoria Melita of Saxe-Coburg and Gotha: Princess Victoria Melita of Saxe-Coburg and Gotha and Edinburgh , later Grand Duchess Victoria Feodorovna of Russia (25 November 1876 – 2 March 1936) was the third child and second daughter of Alfred, Duke of Saxe-Coburg and Gotha, and Grand Duchess Maria Alexandrovna of Russia.
Princess Victoria Melita of Saxe-Coburg and Gotha