Wigger:
You are aware, I'm sure, that the official Regimental name is...
"Stormont, Dundas and Glengarry Highlanders".
This Reserve Infantry unit headquartered in Cornwall, Ontario, Canada, is numbered 19 in the Royal Canadian Infantry Corps Order of Battle.
Raised 3 Jul 1868 as the 59th Stormont and Glengarry Battalion of Infantry. Its Regimental March is Bonnie Dundee...Motto is Dileas Gu Bas...Tartan is Macdonnell of Glengarry.
It is credited with 6 WW I Battle Honours, and 19 WW II Battle Honours.
"Everybody" knows about the nickname, but I have never heard anyone relate just where or when it came to be.
HTH
PS...perhaps our resident historical expert, Mark Tonner, can step in and help here?