NWT Paw Patrol Chase Costume size Small

Brand new in package Chase costume. Size Small, fits sizes 4-6 as per the package. Was too large for my son and I couldn't return it (it has been tried on, just not worn and repackaged in the original packaging). Reviews online say it runs small, but it was too big for my son who wears a 3T. Item includes a pup pap, hat, and jumpsuit. Thin costume-like material (you need to wear something thin and soft underneath). Pup pack straps are velcro.