I bought a set for each boy. I bought a 6 year old 6-7, an 8 year old 7-8 as they always run small. He's put on some weight so is a little stockier and no taller size is necessary for his age. Tried 7-8 on it and it's tight. Worn by a 6 year old, fits perfectly. It's stretchy so it might fit an 8 year old but it was uncomfortable enough for him that it hadn't even been washed. I don't even want to see how much denser it can get after it's gone through the dryer. So you should increase the size.
The Good Day Lab Clean Shield: Ultimate Comfort and Breathability in Tagless 4-Way Stretch Polo
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Boys 3D Graphic Hawaiian Aloha Short Sleeve Dress Shirt Tops with Button Down - Sizes 2-8 Years by Uideazone
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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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Arctix Youth Pants Reinforced: Large Boys' Clothing for Active Adventures
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π₯ Stay Warm and Active with Rocky Fleece Thermal Underwear Bottoms for Boys
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