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.
Dynasty
Prior to the 20th century, dynasties throughout the world have traditionally been reckoned patrilineally, such as under the Frankish Salic law. In nations where it was permitted, succession through a daughter usually established a new dynasty in her husband's ruling house. This has changed in some places in Europe, where succession law and convention have maintained dynasties "de jure" through a female. For instance, the House of Windsor will be maintained through the children of Queen Elizabeth II, as it did with the monarchy of the Netherlands, whose dynasty remained the House of Orange-Nassau through three successive queens regnant. The earliest such example among major European monarchies was in the Russian Empire in the 18th century, where the name of the House of Romanov was maintained through Grand Duchess Anna Petrovna. In Limpopo Province of South Africa, Balobedu determined descent matrilineally, while rulers have at other times adopted the name of their mother's dynasty when coming into her inheritance. Less frequently, a monarchy has alternated or been rotated, in a multi-dynastic (or polydynastic) system – that is, the most senior living members of parallel dynasties, at any point in time, constitute the line of succession.