We love these boots for our 3 year old but always have a hard time sizing her feet.  She has narrow feet and we usually have to either try them on in the store or order a few sizes and then return the ones that don't fit.  We took a leap of faith and ordered an 11 toddler even though she is currently wearing a 9 narrow right now.  They fit her perfectly!  So, perfectly that I hope they last through the winter.  Definitely order 2 sizes larger even if your child has narrow feet.