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.
Imperial Highness
Today, the style has mainly fallen from use with the exception of the . In the past, the style has been applied to more senior members of imperial dynasties, including the French, Turkish, Russian, and Ethiopian imperial houses, among many others. Archdukes of Austria from the Habsburg dynasty traditionally hold the style of Imperial and Royal Highness (), with the "Royal" signifying their status as Princes of Hungary. These styles have been abrogated but are often given out of courtesy. Some members of the royal family of Belgium descending from the Habsburgs do hold it as an official style (the "and Royal" might here possibly be read as referring as well to Belgium). Members of the British Royal Family, theoretically, as the Imperial Family of British India, could have used the title, but did not.