I am a descendant of William Maddox b. 1770 MD, d. 1858 AL.
William and Chandler Maddox were brothers, but not twins. They had another brother named Lawson Maddox, and all 3 of them lived near each other in Tuscaloosa and Fayette counties AL around the 1850's. Their father was almost certainly Benjamin Maddox b. c. 1735 MD, d. 1819 SC, he had 10 sons altogether. Descendants of William, Chandler, and Lawson have all submitted DNA samples to the Maddox DNA project and they all match up, indicating they are probably brothers sharing a common ancestor (see website maddoxdna.com)