Little else is known of Saint-Ruhe's background or family. He married Marie de Cossé, widow of Charles de La Porte, Duc de La Meilleraye. Marie, born in 1622, was many years older and the marriage was childless; she lived until 1710. Although he is not known to have had any legitimate direct descendants, the Rev. Alexander Franklin of St. Mark's Church, Dublin, claimed to have met a great-grandson of Saint-Ruhe serving in the Fitzjames regiment of the Irish Brigade around the time of the French Revolution.