Quite by accident we came across the following for Peter's mother, Isabella Fraser, widow of William Stewart. Died 2nd June 1864 at Middlebridge aged 82 years. Parents given as Donald Fraser, farmer, and Ann Stewart, both deceased. Informant was her son Donald, living at Clachan (of Struan). He's in the census there with his wife and family.
Isabella's trail leads back to the two Donald Frasers, one at Wester Monzie and the other at Raonroy (Runroy), and you can narrow down the pre-1745 marriage as there is an illegitimate daughter, Grissel, by John Seaton in Raonroy
Happy hunting,
Throth (
www.borenich.co.uk)