Hello Pamela,
I am descended from Janet and Thomas Donaldson - my gg grandmother Isabella Donaldson was the eldest child of this couple and I have a lot of detail on the family. I am a bit puzzled by the reference to the first marriage as my records indicate Janet Forfar was approx 16 - 18 when she married Thos Donaldson.
I now live in Melbourne however, I was born in WA and moved east some 30 years ago.
If you would like a gedcom. file of my Donaldson, let me know and I will send it

Regards, Janette Giacobbe