I don't think they lived in Loudon Co.
Married: 10 Dec 1826, Knox Co. TN
Helrey Henderson and L. Wm McClard posted a $1,250 marriage bond.
Souce: TN County Marriages 1790-1950
1840 Roane Co. TN
Hillery Henerson & Family
Died: 1846, Roane Co. TN
Source: Carroll Family Tree, www.ancestry.com
1850 Roane Co. TN and 1860 Roane Co. Elizabeth and children but no Hilrey.
You can do a Google search for Roane County Tennessee Cemeteries and look for his burial in the inventoried cemeteries.
He died too early for any kind of death record. His parents names might be in his death notice, however, there doesn't appear to be a genealogical society in this county. I don't know if the local public library can/will look up a death notice or not.
Since he was living in Roane Co. so early, you might find him and his parents listed in a historical book about Roane Co. You'll find a list of books at TN State Library and ARchives, www.tn.gov/tala/history/county/factroane.htm
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