In review, my Ancestry autosomal DNA "match" to Mrs. Merlyn (Smith) Brown supports that John Richeson Smith (JRS; born 1787 and died after 1870) truly was my maternal ggg-grandfather....and the father of my gg-grandfather Smith W. "Brown." I see no other reason that I would "match" Merlyn, except for that common "JRS connection." Because Merlyn and I are out of different wives of JRS, however, our "shared cM" is not very high....and that "different wives situation" is almost certainly the reason that Ancestry does not show me as a "match" at all to Joseph or Joan (also descendants of JRS), at least not at the new higher "cut-off" of 8 cM that Ancestry now uses.
I also have some "matches" to known descendants of married daughters of John and Ann (Smith) Smith, so that supports John and Ann as having been the great-grandparents of JRS. Also....irrespective of any DNA results....I still see no other reasonable possibility for the parents of the James Smith "Senior" who married Frances Kidd (the grandparents of JRS), other than John and Ann (Smith) Smith.
So, the ancestry of JRS still looks to me to be as follows:
1 Alexander Smith (died 1696) and his unknown wife
2 Lt. John Smith (died 1696) and the widow Mrs. Jane (Cock) Jones
3 John Smith (died about 1740) and Ann Smith (from the neighboring John Smith and Margaret family)
4 James Smith "Senior" (died about 1771). and Frances Kidd
Note: James Smith "Senior" was closely associated with Major Maurice Smith, per several documents, and Maurice (born 1727) was a KNOWN son of John and Ann (Smith) Smith.
5 James Smith "Junior" (died early-1800s) and the widow Mrs. Mary (George) Richeson
Note: James Smith "Junior" was almost certainly the same James Smith who married Kitty Hardy/Hardee in 1793 in Middlesex Co., VA (so his first wife Mary must have died by then). There was an older woman in the home of JRS in 1830....per the Middlesex Co., VA census....so perhaps that woman was his step-mother Kitty (if that woman was not instead his mother-in-law).
6 John Richeson Smith (died after 1870) apparently married three times....a) to unknown (but maybe a Miss Sibley), b) to Fanny M. Stiff and c) to Sarah S. Barrick)
Note: I am not sure what became of the siblings of JRS (per the Christ Church Parish Register) named Catherine George Smith (born 1784) and George Meacham Smith (born 1789; George was last mentioned in the 1800/1801 Will of the Thomas Chowning who had married Elizabeth George....who was a sister of the above-referenced Mary George). I am also not sure if the William J. S. Smith who was mentioned in an 1830 guardian record (the widow Mrs. Elizabeth Bennett became the guardian) was a brother of my Smith W. "Brown" (and hence, a son of JRS), versus if he was instead the son of Smith Bennett named William J. Bennett (and maybe the 1830 guardian record simply recorded the name incorrectly). If he was truly a son of JRS....and truly a brother of Smith W. "Brown”....he seems to have disappeared, but we know that Smith Bennett's son William J. Bennett married Adeline Miller and fathered children, two of whom married the known son of JRS named George H. Smith.