Hi there. I've just came across a partial family tree that my uncle completed back in the 1990's for my grandmother (Jessie Donaldson McGregor Newton) who came from a large family in Thornhill. Her mother was Margaret Donaldson b. 1885, who's parents were Flora McMillan b. Apr 1860 in Beauly, Inverness, and John Donaldson, b. 17 Jul 1857 in Thornhill. Hi parents were James Donaldson b. approx. 1802, and Janet Donaldson b. approx. 1828 in Balquidder, Perthshire. James Donaldson's father was Robert Donaldson, b. approx. 1770's.
Not sure if this helps you at all?
I also recall - similar to the other findings on these posts - that my grandmother told my mum that she was descended from Rob Roy McGregor, and in turn he was descended from King Alpin. She also mentioned something about an aunt who married a Indian from Canada and moved over to stay with him. Her name must have been Janet or something, as my mum - Jane - was named after her.
Hopefully this makes sense and helps a bit.
Not sure how this makes us related, as it's quite confusing.
Best regards,
James McKay