Hi Lisa,
Morrison has a book that tracks the New Hampshire Sinclairs. Book dated
from late 1800's.
http://sinclair2.quarterman.org/books/sinclairgenealogy.html#Morrison
I don't have that book in front of me right now, but I believe he says
the New Hampshire bunch connects to George, 4th Earl of Caithness. But I
don't believe he was 100% certain of that. If indeed that branch
connects to George, the "Wicked Earl," that means your line goes back to
about 600 AD.
The book can be bought at http://www.scotpress.com
They're very helpful.
Steve
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