Lily and I just came back from Petco where we bought the only XSmall Halloween costume they had. Fortunately it's a princess costume and not something icky. I made the poor girl try it on when we got home and you can see for yourselves how she liked it. She'll be wearing it at our chi meetup Halloween party tomorrow, probably without the hat.
P.S. Sorry they're so big - I'll do a better editing job next time, I promise.