Charles "
Charlie"
Kelly is a fictional character on the
FX series
It's Always Sunny in Philadelphia, portrayed by
Charlie Day. Charlie is co-owner at Paddy's (although he later sells his shares) and a childhood friend of
Mac and
Dennis. He is also
Frank's roommate and possibly his biological son. He is addicted to huffing various glues and paints, and also does not know how to read or write.