He appointed as regent, Margaret, duchess of Parma, a natural daughter of Charles V.
Robert was a man of learning, devoted to literature, and a generous patron of literary men: he befriended the poet Petrarch, who admired the king so greatly as to express the wish to see him lord of all Italy; while Boccaccio celebrated the virtues and charms of Robert's natural daughter Maria, under the name of Fiammetta.
DIANE DE FRANCE (1538-1619), duchess of Montmorency and Angouleme, was the natural daughter of Henry II.
In his absence he left Lucrezia as regent, offering the astounding spectacle of a pope's natural daughter in charge of the Holy See.
MARIE JEANNE BECU DU BARRY, COMTESSE (1743-1793), French adventuress, mistress of Louis XV., was the natural daughter of a poor woman of Vaucouleurs, and was born there on the 19th of April 1743.
Dupin de Francueil, a farmer-general of the revenue, who married the widow of Count Horn, a natural son of Louis XV., she in her turn being the natural daughter of Maurice de Saxe, the most famous of the many illegitimate children of Augustus the Strong, by the lovely countess of Konigsmarck.
Orazio, Pierluigi's third son, was made duke of Castro when his father became duke of Parma, and married Diane, a natural daughter of Henry II.
He second wife was Joanna Bridges, said on very doubtful authority to have been a natural daughter of Charles I.