All of the troops were, affectionately, called boys. Some of them literally were. Younger than sixteen, anyhow, including the youngest casualty of the Battle of Fort Sanders, a fourteen-year-old drummer boy of the Second Michigan.
But a few drummer boys half that age were sometimes recruited on both sides and, when they weren’t busy running and playing about the camps, had the job to make the drum taps and the long rolls that marked the days and the duties of the older “boys.”
They also could be found assisting the surgeons with cleaning up acreage for places to treat the many wounded, and helping carry stretchers, as related here in the July-December 1861 edition of the American Medical Times by a surgeon with the 31st New York.
Period article via Bull Runnings.