My son just turned 5 and I bought a 4T. It fits perfectly and not tight, just comfortable. He doesn't like coarse fabrics, but this one is soft and not flimsy either. He is very fond of dinosaur design. I would recommend these products.
Pack of 6 Baby Soft Cotton Underwear for Little Boys - Dinosaur Briefs, Toddler Shark Undies, Children Truck Panties
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Boys' Adidas Active Sports Tricot Athletic Clothing
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