what to wear for a rehearsal dinner

So we were in Ohio this weekend for the wedding of my husband's brother, and it was kinda fun to be more than just the photog.
Since le husband was in the wedding party, I attended the rehearsal and dinner afterwards, and this was my outfit.



dress: originally from Anthro; I found it at a reseller for less than $20
shoes: Oh Deer!
hat/earrings/bracelet: Gabriel Brothers
I'm not sure what caused the expression. I look like I just ate a pickle!