I have the son of John L. and Peggy Leavell as Thomas S. Leavell, born 1830 in Belton, Anderson, South Carolina, died March 23, 1896 in Cowpen Community, Lauderdale, Alabama. He was a reverend.
I'm willing to believe someone misread a handwritten S for L or vice versa. (In one printed census index, a Levell family was listed as Sewell!) I've also seen the husband of Clarinda Garrett listed as Thomas Levels or Thomas J. Leavell, and as born in 1833!
What makes you think that Clarinda's husband is the same man as the son of John and Peggy?