Virginia started recording births 1853-1896 so don't look for birth records.
I'd look for James will/probate records which should list all of their children.
The Virginia Archives, www.lva.virginia.gov/public/localresults_all.asp?CountyID
has a general index to wills 1744-1930 and wills starting in 1748.
You also might find these records in FamilySearch, Catalog. Successful Searching!