Thomas Donaldson

Anthea, in case you or your Dad want to check here for possible death records if Grandpa is passed on by now, which is a very high possibility considering if he was 35 back then and therefore born around 1910-ish:

Death Registrations after 1936 are still held by the Office of the Registrar General.
Contact:

Office of the Registrar General
189 Red River Road
P.O. Box 4600
Thunder Bay, Ontario
Canada P7B 6L8

Tel: 416-325-8305
1-800-461-2156 (toll-free in Ontario