Then down from that side, his grandfather and namesake, Captain Henry C. Mustin, was the first of many Mustins to attend the United States Naval Academy as a member of the Class of 1896. He was Naval Aviator #11 and considered by many to be the father of naval aviation, having established Naval Air Station Pensacola, being the first to be catapulted off a ship underway, and being in command of the aviation detachment that fought at the Battle of Veracruz, which was the first time that any U.S. aviator of any service was fired on by ground forces. Admiral Mustin's grandmother, Corinne Mustin, was a first cousin of Wallis Simpson, the Duchess of Windsor. When his grandfather Henry Mustin died, she remarried Admiral George D. Murray, Naval Academy Class of 1910. Murray was captain of the during the Doolittle Raid and at the Battle of Midway, and was a close friend of Admiral Chester Nimitz. After the Japanese surrendered to the United States on board , Admiral Nimitz signed a copy of the picture to Admiral Murray with thanks. At the end of the war, he was the commander of the Mariana Islands, and accepted the Japanese surrender of the Caroline Islands aboard his flagship, the cruiser . Admiral Mustin's great-uncle was General George Barnett, Naval Academy Class of 1881 and 12th commandant of the U.S. Marine Corps. Mustin was the third generation of his family to attend the US Naval academy. His father, Vice Admiral Lloyd M. Mustin, was Naval Academy class of 1932. His brother and one of his sons also graduated from Annapolis. Mustin said: "I’m the class of ’55, my brother, Tom, is the class of 62, and my youngest son, John, is the class of ’90."