Question: Who's son concluded a set of treaties which ended the American Revolutionary War?

Vice-Admiral Robert Plampin (1762 – 14 February 1834), was a British Royal Navy officer during the late 18th and early 19th centuries, serving in the American Revolutionary War, the French Revolutionary Wars and the Napoleonic Wars, but best known for his time as commander of the British colony of Saint Helena in the South Atlantic during the period when former Emperor Napoleon Bonaparte was imprisoned there.  Born into a Navy family, Plampin went to sea at age 13 and fought throughout the American Revolutionary War, based principally in the Caribbean Sea.  During the French Revolutionary Wars, Plampin served in a number of ships with mixed success, once being involved in a shipwreck and twice serving ashore during sieges.  After the Peace of Amiens, Plampin took command of the ship of the line HMS "Powerful" and operated successfully in the Atlantic and the Indian Ocean.  In 1816, following the defeat and capture of the French Emperor, Plampin was placed in command of the squadron at the Cape of Good Hope, which also had responsibility for Saint Helena, which Plampin regularly visited and had numerous conversations with Napoleon. <SEP>  He was the eldest son of William Petty, 1st Marquess of Lansdowne, known to history as the Earl of Shelburne, the British prime minister who concluded the Peace of Paris recognising American independence, by his first wife, Lady Sophia Carteret. John Henry Petty, 2nd Marquess of Lansdowne (2 May 1765 – 15 November 1809) was a British peer and politician. <SEP> The Peace of Paris of 1783 was the set of treaties which ended the American Revolutionary War.  On 3 September 1783, representatives of King George III of Great Britain signed a treaty in Paris with representatives of the United States of America—commonly known as the Treaty of Paris (1783)—and two treaties at Versailles with representatives of King Louis XVI of France and King Charles III of Spain—commonly known as the Treaties of Versailles (1783).  The previous day, a preliminary treaty had been signed with representatives of the States General of the Dutch Republic, but the final treaty which ended the Fourth Anglo-Dutch War was not signed until 20 May 1784; for convenience, however, it is included in the summaries below. <SEP> The Treaty of Alliance with France or Franco-American Treaty was a defensive alliance between France and the United States of America, formed in the midst of the American Revolutionary War, which promised mutual military support in case fighting should break out between French and British forces, as the result signing the previously concluded Treaty of Amity and Commerce.  The alliance was planned to endure indefinitely into the future.  Delegates of King Louis XVI of France and the Second Continental Congress, who represented the United States at this time, signed the two treaties along with a separate and secret clause dealing with future Spanish involvement, at the hôtel de Coislin (4, place de la Concorde) in Paris on February 6, 1778.  The Franco-American alliance that would technically remain in effect until the 1800 Treaty of Mortefontaine, despite being annulled by the United States Congress in 1793 when George Washington gave his Neutrality Proclamation speech saying that America would stay neutral in the French Revolution.