Complex sentence: She and her husband, the Duke of Orléans, were the founders of the modern House of Orléans--their only surviving son, Philippe II, Duke of Orléans, being the Regent of France during the minority of Louis XV of France.
Split into simpler sentences: She and her husband, the Duke of Orléans, were the founders of the modern House of Orléans. Their only surviving son, Philippe II, Duke of Orléans, was the Regent of France during the minority of Louis XV of France.