My son is 84 kg, 9 years old and about 50 inches tall. Last summer he wore a 10/12 bottom and a medium/large top. I ordered XL because I think his waist measurement is a bit larger than average and/or boys underwear in general is just weird, but I digress. XL seemed to fit, but not for long. I can't tell if it was because my son had gained a few pounds, or his lower body had shrunk a bit, or both. This will definitely hold up for many washes (in cold weather) and I tumble dry our clothes. I am happy with how they have held up, not stretched or come apart at the seams.
π Russell Athletic FreshForce Protection: Boost Your Boys' Performance with Assorted Clothing
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π Brix Boys Long Sleeve Tees - Optimized Clothing for Boys
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Comfortable & Durable: Lucky & Me Noah π©² Boys Boxer Shorts 5 Pack - 100% Cotton Tagless Underwear
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Comfortable & Practical City Threads Underwear: Sensitive-Friendly Boys' Clothing
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Boys' Adidas Active Sports Tricot Athletic Clothing
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π Bold Pack Sleeve Active Hoodie Sweatshirt Set for Boys' Clothing - Stylish and Comfortable!
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Waterproof Cozy-Dry Rain/Snow Pants for π§ Kids by JAN & JUL, with Fleece Lining
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Arctix Youth Pants Reinforced: Large Boys' Clothing for Active Adventures
46 Review