[1][2][3] After his parents' early deaths, young William was adopted by his paternal uncle, W. Butler Duncan I.
[4] His adoptive father (and uncle) was born in Edinburgh and became a banker in New York and chairman of the Mobile and Ohio Railroad.
[7] After graduation from the Naval Academy, Duncan stayed in the U.S. Navy for two years until 1884, serving on the USS Vandalia.
In 1891, he was one of the organizers of the 1st Battalion of the New York Naval Militia, and served as commanding officer of one of its divisions.
[9] Together, Blanche and William were the parents of four children who survived to adulthood, including: After his death on March 30, 1933,[1][7] William Butler Duncan II was buried at sea from the USS Cole with full naval honors.