NWT- Cozy slippers! Boys 4-6 (girls can wear too!)

Purchased from another Posher and they just don’t fit my son. I miss measured! These are so cute and cozy! Skull design is perfect for boys or girls! Says boys size 4-6. But, I think they may be sized wrong. My son is a size 3 and these were too small. So I’d say these will fit a boy from age 3 years to 5 or 6 years old.