Yes, Frank is the same size as the pageant contestants. You've gotta love that.
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It's all about the child beauty pageant business this week on It's Always Sunny in Philadelphia, as the whole gang gets involved.
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It's Always Sunny in Philadelphia Season 7 Episode 3 Quotes

I am not gonna diddle your kids.

Frank

How would you win pageants? Did you have a different face?

Mac [to Dee]