Always has been Stuey, think it goes back to their Rangers days, now I'm not entirely sure Kenny was at Ibrox at the same time as Fergie, before he went to Parkhead, but it's possible, but of course their both Weegies(Glaswegians) so the respect would be there anyway.
I think Kenny was a youth player at Rangers back then, but was then offered the chance at Celtic by the Legendary Jock Stein.
Erm, Kenny lived in Govan, near Ibrox, for part of his childhood, but I don't think he ever played for Rangers' youth teams. I know you've been supporting Liverpool for eons longer than me, but I have a lot of Rangers' supporters from my mother's side of the family and I think Kenny was always looked at as one the club missed on (like the miss of the century).
Kenny DID, however, sign on to be some kind of club advisor/executive for Rangers in the late 90s or early 2000s and that fact is almost totally expunged from history, but it did happen. He was supposed to attract great talent to the club from all of his connections.
Don't worry, Celtic fans, I know all he really did for Rangers was play golf at David Murray's course and get some moneybag types to join him for a while as a representative of a sporting company. But he did join the executive team at Rangers for a bit. I don't think it lasted even a year. But I don't think he ever played for a Rangers youth team.
Here's an article from back then.https://www.irishtimes.com/sport/daglish-to-aid-rangers-1.119006