Louis Alphonse, Duke of Anjou
Their father has conferred upon them the historic French titles of, respectively, Duke of Burgundy ("duc de Bourgogne"), and Duke of Berry ("duc de Berry"). (In Spain, the twins are "Don" Luis and "Don" Alfonso de Borbón Vargas). Prince Louis, as Legitimist Dauphin of France, is expected to succeed his father as head of the French royal house, the senior Bourbon/Capetian line, in Legitimist reckoning. However, under Spanish law, and assuming Felipe VI does not in future father a son, the Spanish crown will be inherited by his elder daughter Leonor, Princess of Asturias, who will become queen regnant, and if Felipe does have a son, that son will inherit the Spanish throne regardless of the genealogical seniority of the Anjou branch. Louis and Alphonse were baptised on 5 September 2010 at St Peter's Basilica in Vatican City. Louis' godparents were Arancha Martínez-Bordíu and Francisco D'Agostino and Alphonse's were Amparo Corell de Trenor, and Lorenzo Perales.
Maison du Roi
The Maison du Roi (, "The King's Household") was the name of the royal household of the King of France. It comprised the military, domestic and religious entourage of the French royal family during the Ancien Régime and Bourbon Restoration. 
The exact composition and duties of its various divisions changed constantly over the Early Modern period. Officers of the "Maison du Roi" were directly responsible to the "Grand maître de France" (Chief Steward). Starting in the 16th century and then from the 17th century on, the "Maison du Roi" was overseen by a ministry, the "Département de la Maison du Roi", directed by a secretary of state, the "Secrétaire d'État à la Maison du Roi". The structure of the "Maison du Roi" was officially reorganized under Henry III in 1578 and 1585, and in the 17th century by Jean-Baptiste Colbert.