Malcolm -- the liner notes for "Mill O'Tifty" ("The World's Room", Green Linnet Records, 1999) state:

Also known as "Andrew Lammie", this traditional "muckle ballad" tells the true story of Agnes Smith, a miller's daughter who lived near Fyvie in Aberdeenshire. She fell in love with Lord Fyvie's trumpeter, a man below her station, then compounded her troubles by spurning his employer. For this "sin" she was killed by her brother. Her gravestone still stands in Fyvie kirkyard, dated 1673."

Cheers,
Michael