My ancestry contains a Dougal Campbell and wife Mary who begat a James Campbell. My info (inherited from my dad's genealogical researches) indicates that James was born 23 Aug 1745 in Berkeley, Va. and died 23 Apr 1817 in Martinsburg, Va. His wife was Sara, born in 1747 and died 1817 in Berkeley, Va.
I have one record of a daughter, Mary Campbell, born 15 Aug 1773 in Mercersburg, Pa. died 7 Jul 1828. She married Joseph Pollock, and they had a son, James Campbell Pollock.
But something I found today sounds like what you want. In searching for Dougal, I came up with a result in the Gene Pool Individual Records of a Dougal Campbell, born 31 Aug 1777 in Berkeley County, Gerrardstown, Va., to parents James Campbell and Sarah. I'm guessing that this Dougal was named after the father of James (assuming that info is correct and not some temporal inversion). The ages are right.
The record goes on to say that this Dougal married a Sara Wallace Lyle, and he died 23 Dec 1844.
This same Dougal is probably the guy listed as a Major in 1 Reg't (Taylor's) Virginia Militia in the War of 1812 service records.
The DAR lineage book lists a Dougal Campbell marrying a Sara Wallace Lyle (1788-1875), but I've found errors in the DAR books for a cousin (?) of mine, Thomas Hugart.
Let me know if you've found other information since you've posted your note.
Jacob