"Madeleine de Bourbon-Busset (1898–1984), daughter of the count of Lignières and Jacques's fourth cousin once removed, married in 1927 a royal Bourbon relative, Xavier, titular duke of Parma and Carlist pretender to the throne of Spain. Although Madeleine brought as dowry the chateau of Lignières, at the time this marriage was not accepted as dynastic by the titular Duke, Xavier's elder brother, obtaining dynastic recognition retroactively around the time of the engagement of Xavier's eldest son to the daughter of Queen Juliana of the Netherlands in 1964.
As wife of Xavier, Madeleine was, however, proclaimed Queen consort of Spain by the remaining Carlists in 1952. Widowed in 1977, she remained a staunch adherent of her husband's Carlist principles. She excluded her elder son from the funeral of her husband as disloyal to his father's traditionalist Carlism, recognizing instead the claim to Carlist leadership and to Lignières of her younger son Prince Sixtus Henry of Bourbon-Parma, (self-proclaimed) duke of Aranjuez, who continued the rivalry with his brother as Carlist pretender.
A senior male-line descendant of the Bourbon-Busset was the French writer Jacques de Bourbon-Busset (1912–2001), member of the French Academy. President Charles de Gaulle was once quoted telling him: Had it not been for the decision of King Louis XI, you might well be head of state of France today, instead of me."
Also:
"Xavier's marriage to Madeleine was recognised as dynastic by the Carlist claimant to the throne of Spain, Alfonso Carlos, Duke of San Jaime, who was married to the sister of Xavier's mother. However, Xavier's half-brother Elias – who was regent for their handicapped brother Duke Enrico of Parma – did not recognise the marriage as dynastic regarding the succession to the ducal throne of Parma. The reason for this lack of dynastic recognition was in part Madeleine's ancestry, but it was also influenced by other political and family differences. During the 1920s and 1930s Elias and Xavier were on opposing sides of a family legal battle over the ownership of the Château de Chambord. Elias had also recognised Alfonso XIII as constitutional king of Spain, in spite of the fact that his father Robert had supported the Carlist claimants.
In 1961 Elias' son Duke Robert II of Parma recognised the marriage between Xavier and Madeleine as dynastic regarding the succession to the ducal throne of Parma."
And dynastic squabbling:
"On 20 April 1975 Xavier abdicated as Carlist king in favour of Carlos Hugo. His younger son Sixtus Henry opposed the succession of Carlos Hugo and presented himself as the "standard-bearer" (abanderado) of traditional Carlism. Xavier issued a declaration affirming that his abdication had been voluntary, and that Sixtus Henry had separated himself from Carlism. The battle between Xavier's sons continued with each claiming their father's support. Carlos Hugo was supported by his three unmarried sisters, while Sixtus Henry was supported by his mother.
Carlos Hugo accused Sixtus Henry of having abducted Xavier who was then in hospital. Sixtus Henry published a declaration from Xavier dated 4 March 1977 in which Xavier re-affirmed his support for traditional Carlism. In this document Xavier condemned the socialist form of Carlism which he described as "a very serious doctrinal error". Three days later on 7 March 1977, Xavier's daughter Cecilia took Xavier out of hospital in order to take him to mass. On this occasion Xavier signed another declaration published by Carlos Hugo in which he confirmed Carlos Hugo as his heir. The next day Xavier's wife Madeleine published a declaration condemning Carlos Hugo and Cecilia.
On 7 May 1977 Xavier died of a heart attack in a hospital at Zizers near Chur in Switzerland; he had been visiting his sister the Empress Zita of Austria. Xavier was buried at St. Peter's Abbey, Solesmes where three of his sisters had been nuns."