'Always Sunny' Star Charlie Day New Season Is HUGE ... for Mac

8/23/2011 12:02 AM PDT

"It's Always Sunny in Philadelphia" Star Charlie Day -- The Skinny on Next Season

While "It's Always Sunny in Philadelphia" star Charlie Day is traveling the world promoting a movie -- his co-star Rob McElhenney is busy fattening up for the next season of the show (seriously). Does fatter = funnier?

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