Saxe-Coburg and Gotha
9 years, 121 days
https://en.m.wikipedia.org/wiki/Princess_Elisabeth,_Duchess_of_Brabant
Philippe
Princess Elisabeth, Duchess of Brabant
Philippe was born on 15 April 1960 at the Belvédère Castle in Laeken north of Brussels. His father, Prince Albert, Prince of Liège (later King Albert II), was the second son of King Leopold III of Belgium and a younger brother of Baudouin. His mother, Paola, Princess of Liège (later Queen Paola), is a daughter of the Italian aristocrat Fulco VIII, Prince Ruffo di Calabria, 6th Duke of Guardia Lombarda. His mother descends from the French House of La Fayette, and the king is a descendant of Gilbert du Motier, Marquis de Lafayette, and Marie Adrienne Françoise de Noailles.
Mathilde d'Udekem d'Acoz