I spent some time this winter trying to find out this very thing, and GOOD LUCK to you.I put some of what I found online http://www.leesgenes.com/stevenson/index.htmhttp://www.leesgenes.com/stevenson/index.htm but I got bogged down again.
Anyway, in brief - I also do not think Adam was Susannah's father. The best possibilities I have found are:
Andrew - mentioned in Chalkley 1748-1766 Possible parent of Susanna? witness along with Hugh Lusk, who is our best guess for father of Samuel, Susanna's future husband. - Clan 2
John - mentioned in Chalkley 1741-1794, with later lawsuits. There are at least 8 different Johns, so please excuse me if I am too boggled to separate them. ONE lived near John/Hans Bomgardner, for whom Thomas Godfrey worked, so he is a good candidate for father of Susanna. Another, possibly the same one?, had close connections with Andrew Stevenson, who was mentioned along with Hugh Lusk, so there is another good possibility. - Clans 1, 2 AND 3
Robert I, possible brother of John, William, Thomas and David. Probably married twice - 2nd wife Martha Rankin, widow of George. A possible father of our Susannah - his will does mention "living daughters."
The "clans" mentioned are three different branches of Stevensons, identified by Mike Taylor and his co-researchers:
Clan 1) - In what is now present day Rockingham Co. VA. Supposed brothers David, William, Robert, Thomas, and John. I think I - this is Mike speaking - descend from John (or maybe Thomas, or maybe Robert). David, William, Thomas, and Robert were in the vicinity of the Old Augusta Stone Church. John was about 3 miles SE of Harrisonburg. He called his place Meadow View. David went to York Co. SC about 1763.[Actually David probably went to North Carolina first.]
Clan 2) - George, John, and Andrew Stephenson were down in Bordens Grant about 10 miles NE of Lexington.
Clan 3) - John and Martha (Warwick) Stevenson. They were west of the SW corner of Borden's Grant. Up Kerr's Creek and maybe even as far west as in the 'Pastures'.
ONE OTHER THING - I have mentioned Hugh Lusk as the best guess for the father of Samuel - that is no longer the case.The DNA testing makes our Lusks NOT related to the Chester Co, PA Lusks, so we have to reconsider this too - so some of my reasoning about possible parents of Susannah is based on a mistaken premiss.
I would really like to know what conclusions you come to - this has been bothering me for years! My email - spaces added etc in an attempt to foil the bad guys - alethea 47 AT charter DOT net