Has DNA testing come up trumps?

Early days yet, but indications are that we may be on the way to proving that Robert FAIRBAIRN,  married to Kate SCOTT and emigrated to Ontario around 1827/8 is indeed a son of Archibald and Alison (CROSSER) FAIRBAIRN.
One of my closer previously unknown DNA matches appears on a segment of dna that I share with a known double cousin (4C1R and 5th, as he descends from both James and from David, sons of Archibald and Alison).
"Do you have any known FAIRBAIRN ancestry" I asked.
"Yes, a Mary Catherine FAIRBAIRN married to Peter Nelson KELLER."
Now I just happen to know that Mary is Robert's granddaughter.

Although I don't yet know how my match links to Mary, or whether there's another line in her ancestry that could account for this match, I'm pleasantly hopeful we're finally on our way to proving my long held theory about Robert being "family".
Updates on Mary's family will now ensue.
Confirmation may shortly be forthcoming as the kit from another descendant of Robert & Kate's is en route back to the lab.
It would still be great to find a direct male line FAIRBAIRN descendant of Robert's willing to do a y_DNA test to quickly and more easily prove this link though!

Moral or medical judgement?

(From an 1866 death certificate)

Found during investigations into a dna match between a descendant of a FAICHNEY/McTAVISH family from Dunblane and two of the extended HENDERSON/McEWAN family tree FamilyFinder participants.

If there are any dna tested descendants from the family of Fergus FAICHNEY and Mary McTAVISH who married at Dunblane in 1842 I'd love to hear from you to help rule in or out that this is the line where the match comes from.

Or, for that matter John McTAVISH and Margaret McDIARMID who married at Killin, Perthshire in 1811.