Virginia didn't start to record births until 1852 so that option is out.
Do you have an actual copy of their marriage record? Both sets of parents might be on it. If you don't have a copy, the Montgomery County records are in the Virginia Archives, www.lva.virginia.gov/public/local/results_all.asp?CountyID=V...
You also might be able to find this record in FamilySearch, catalog.
If the parents aren't listed, I'd look for their newspaper marriage announcement. The Virginia Library has old newspapers.
i'd look for any applicable military records of his. If you do a Google search you can find a list of our military conflicts/wars. Those records are in Fold3 which most larger, public libraries provide access to if you have a local library card.
You can also order those records from the U. S. Archives, archives.gov.
Do you have a copy of his newspaper death notice? If not, I'd contact the historical and genealogical societies and public library in Harlan County, KY for a copy/scan. His parents might be in it.
Another option is to look for a family tree which contains that info and validate that the info is correct.
William Wilson, b. 1776 British Colony of Virginia; married Nancy Banks, 19 Feb 1798 in Garrard Co. KY. Nancy died in 1850 in Marion Co. MO. William died 1847 in Marion Co. MO.
Source: Nutter and Hartwell family tree, Ancestry
Married: 19 Feb 1798, Garrard, KY
Source: KY Compiled Marriages 1802-1850
1850 Warren, Marion, MO
Robert J. Jones, b. KY, 46
Lucinda, b. KY, 40
Thomas N., b. KY, 20
John H., b. KY, 18
Brien L., b. KY, 15
Sarah E., b. MO, 9
Mary J., b. MO, 5
Edmund, b. MO, 3
Nancy Wilson, b. MD, 84
I'd look for William's probate records in Marion Co. MO to see if Daniel is listed in those documents. Successful Searching!