Perfectly normal my 4 year old only wears a 6 in toddlers and my son who is 2 wears a 6 as well my daughter was in a 2 until she was almost 3

Infant size 2. She's barely standing and isn't walking at all yet, so I'm thinking it's because her feet are so small.

is she in infant size 2 or preschool size 2. my son is size 6 toddler