Ok ... how old was your son when he wore them? I'm trying to fit a soon-to-be 5 year old and everything I buy for him has a problem fitting. Maybe he's just an odd kid .. lol
My son is 9, but born with Down Syndrome and an extremely picky eater so he weighs about 55 lbs soaking wet! Here is a link to the shoes on the Target website, maybe it'll help?
I am so glad that helped! It's really hard to know what size anything to buy anymore with every brand using a different sizing system! I know that my son can wear a 7 in Carter's and it fits perfectly, however in Children's Place it is too big!!! Good luck on the auction and thanks, raising a special needs child is definitely a challenge, but he is a real joy.