I got this costume in size 6-12 for my daughter who is 9 months old (19 lbs and 27 inches tall) and it fit her great!  There wasn't a TON of room length wise so if you have a tall baby, go one size bigger.  I was able to use the hand wash cycle in the washing machine and air dry without any problems.  Something a little strange about it, there are two tails - one on the back and one on the hat!  The one on the hat is only sewn on with two stitches so I just removed it so it wouldn't look so weird.  It comes with an adorable carrot rattle as well.  I had so many people tell me how cute she looked and even one that said it was the cutest costume they'd ever seen...she was a hit in this one!  I highly recommend it, great fit and great quality!!