Looking for "James Ewart Hill" and "Robert Ewart Hill"

These sons of Sarah Ewart 1768-1801 and Thomas Hill (probably 1769 to 1840s) were alive in Lincoln County, NC, in 1818, both over 21, born in 1787 or the next years, but before 1801. They had prosperous Lincoln County connections. What happened to them? If you leave out the middle name "Ewart" you are left with something pretty near "William Smith" when you are hunting in the census tables.