This represents the boy < 10 in the 1820 census, and the elder of the two boys 10-14 in the 1830 census. I am assigning the name Nathaniel to this son, but it could instead be the name of the younger of the two boys 10-14 in 1830, or even of the son under 5 in 1830. Two of these boys apparently died young, as only three sons (Nathaniel, Benjamin F., and James O.) are mentioned in their father's will.