Hi, Erving, Don't know whether you are still following.
I believe James Briggs, father of Charles W., was married to Polly Arnold, then Rebekah Johnson:
Virginia, Marriages, 1660-1800 Birth, Marriage & Death Name: James Briggs Spouse: Polly Arnold Marriage: 10 Feb 1794 - Mecklenburg County, Virginia
Virginia, Marriages, 1740-1850 Birth, Marriage & Death Name: James Briggs Spouse: (Mrs.) Rebecca Johnson, widow Marriage: 16 Nov 1818 - Mecklenburg, Virginia
I'm tracking the Briggses in Tennessee and Mississippi to see whether I can find a connection to James L. Briggs of LaFayette County, b. 1808 VA. It's a big problem that some Virginia censuses are missing.