Marsan was created a knight of the Order of the Holy Spirit, the most prestigious decoration of the Ancien régime on 2 February 1756.

His older sister Louise Henriette Gabrielle married the Duke of Bouillon.

His older brother, Gaston Jean Baptiste Charles married Marie Louise de Rohan, future Governess of the Children of France.

Camille himself married Princess Hélène Julie Rosalie Mancini (1740–1780), styled as Mademoiselle de Nevers.

She was the daughter of Louis Jules Mancini Mazarini, Duke of Never, a man of letter and his wife Hélène Françoise Angélique Phélypeaux de Pontchartrain (1715–1781), herself a daughter of Jérôme Phélypeaux de Pontchartrain.