I think what you're going to have to do is make a copy of the eyes, and use the liquify filter to make the copy of the eyes "smile" -- push up on the eyebrows, squint up on the bottom lids.  If you look in a mirror at yourself, go from a blank stare (or distressed frown, like No. 146) and then smile hopefully, you'll be able to see the changes you will need to make. 

There are lots of tutorials on the web on how to use the liquify filter to make pictures smile.  If you do a Google search, I'm sure you'll find something that will help you accomplish your goal.