I realize that you posted queries several years ago, but I was wondering whether you were able to determine information on your McDonald family members.
I have just learned that my great grandfather - Francis (Frank) McDonald married Mary Gannon in 1904 in Cornwall.
Francis' parents were Angus McDonald and Catherine (maiden name McDonald also). In the Stormont and Glengarry areas there were in fact two marriages of an Angus and Catherine McDonald, both in 1883, and I am not certain which one would be the correct couple.
Any chance you have the Francis and Mary Gannon "twig" in your tree?
If you could help me narrow things down it would help.
One of the Angus and Catherine marriages were at St. Raphael's November 5, the other was at St. Finn's in Alexandria on Feb. 6 the same year.