Princess Marie-Esméralda of Belgium, Lady Moncada (born 30 September 1956), is a member of the Belgian royal family. She is the half-aunt of King Philippe of Belgium and Henri, Grand Duke of Luxembourg. Princess Marie-Esméralda is a journalist, author and documentary-maker. She is also an environmental activist and a campaigner for women’s rights and indigenous people’s rights. Princess Marie-Esméralda is the youngest child of the late Leopold III of Belgium and his second wife, Lilian Baels, Princess of Réthy. Her full siblings are the late Prince Alexandre of Belgium and Princess Marie-Christine of Belgium. Her half-siblings include the late King Baudouin of Belgium, former King Albert II of Belgium (who is also Marie-Esméralda's godfather), and the late Grand Duchess Joséphine-Charlotte of Luxembourg from her father's marriage to his first wife, Queen Astrid. Princess Marie-Esméralda of Belgium married Sir Salvador Moncada, a Honduran-British pharmacologist, in London on 5 April 1998. They have a daughter, Alexandra Leopoldine Moncada (born in London on 4 August 1998), and a son, Leopoldo Daniel Moncada (born in London on 21 May 2001). Princess Marie-Esméralda is a journalist and author, writing under the name Esmeralda de Réthy. After studying law at the Université Saint-Louis - Bruxelles, she graduated in journalism at Université catholique de Louvain in Louvain-la-Neuve and then moved to Paris to pursue her career, working freelance for international magazines. Her book Christian Dior, the Early Years 1947-1957 focused on the career of Christian Dior and was published in 2001 by Vendome Press. Esmeralda then went on to write several books about her late father King Leopold III using archival material such as letters and photos. Her book Léopold III, mon père was published in 2001, followed in 2006 by Leopold III photographe, both published by Racine. In these books she writes about her father’s expeditions, and his passion for nature, science and photography, rather than the Belgian royal family (Racine).