Hmm it appears so! Looks like it comes from a French phrase. Maybe it's common up near Canada? Which might explain since I have yet to visit a couple of friends I have that live there. Never heard them use it either but oh well.
Perhaps you are too young. From the first source it was a favorite of Johnny Carson:
": The origin of this, I believe, is the
French phrase, "C'est à rire," which, translated literally as "It is to laugh," caught Johnny Carson's fancy. He repeated it often on his show, in a low-key manner, meaning roughly, "That's funny" (i.e., humorous), but often without great enthusiasm."
I edited my previous post and mentioned that you did not seem to have caught my reference to Muphry's Law.