I ordered this for my nephew who is quite strong for his age (3yrs 48lbs). He usually wears a size 5 so I ordered him a size 6/7. This size fits him perfectly. The elastic waist of the shorts was very stretchy and didn't wrap around the legs, which could be an issue for him. Since it was a larger size, we ended up making shorts of about 2 inches. The material of this three piece suit is thin, mind you, but I didn't mind because my nephew gets hot easily. All in all a great buy for the price. I am posting a photo of a size 6/7 suit with Target brand clothing for comparison.
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