Willie,
Thanks, that brilliant - your info has ruled out this lady.
The OPR entry reads "Born to John Pirie, had farm at Birse, and Margaret Glennie. 'John Pirie a married man sometime residing at Tourmill (or Fourmill), Premnay and Margaret Glennie, daughter of Robert Glennie. Matriach had a natural child at Cairnmore Parich of Auchindoir on 7th day of July 1845 - Ann' ".
I can't find John, nor Robert, and the right Margaret is out there somewhere.
So far I have found 3 children to MG
William Taylor 21/11/1839 Clatt by Alexander Taylor.
Ann Pirie 7/7/1845 Auchindoir, Clatt by John Pirie. **
Isabella Cobb 20/9/1849 Clatt by Alexander Cobb.
I have at least found 1 Robert Glennie who married a Jean Valentine, but nothing to link them.
** Ann married Charles Skene in 19/11/1869 Tarland.
So I will have to think what the next move is.
Again thanks Dad_of3.