I honestly think he's smiling like in a you-know-what way that because when Grandad got a date through the internet she came over to his house and at dinner she reviled she was a deadly Kung Fu master(and crazy) and then Riley says:

"So you like John Claude Van Dam? D@mn." **smiles**


Here's the episode(I highly recomend it for a great laugh!) : [link]
(fourth video across on the first row *remember that the video's change weekly so it might not be there anymore*)

Here's another one (that's not where I got it)--->[link]

Riley belongs to Aaron McGregor(c)