This costume looked great and delivered!  We had 2 nights of candy collecting and the costume is holding up very well. As for fit, my daughter is about 45 lbs and 46 in. tall.  We ordered a size 8.  The costume fit a bit loose and had to be pinned up in the back because the front was too low on her chest.  The overall length was good, and pinning it up helped ensure she wouldn't be tripping all over her "tail" while trick or treating.  The headband that is included stays in place pretty well also.  Another bonus- there was no complaining about itchiness from the material! Overall I really loved this costume!