From wikipedia:
"Elias of Bourbon, Titular Duke of Parma (1880-1959) was the head of the Bourbon House of Parma.
His parents were the deposed Robert I, Duke of Parma and his first wife Maria Pia of the Two Sicilies, daughter of Ferdinand II of the Two Sicilies.
Despite loss of his throne, Robert and his family enjoyed considerable wealth, traveling in a private train of more than a dozen cars among his castles at Schwarzau am Steinfeld near Vienna, Villa Pianore in northwest Italy, and the magnificent château de Chambord in France.
Less than four months after Duke Robert's death in 1907 the Grand Marshal of the Austrian court declared six of the children of his first marriage legally incompetent, at the behest of Duchess Maria Antonia, Robert's second wife and Elias' stepmother. Nonetheless, Robert's primary heir was Elias, Duke of Parma, 1880-1959), the youngest son of the first marriage and the only one of those sons to father children of his own. Elias also became the legal guardian of his six elder siblings. Although the eldest half-brothers, Sixte and Xavier, eventually sued their half-brother Elias to obtain a greater share of the ducal fortune, they lost in the French courts, leaving the issue of Robert's second marriage with modest prospects."