I think I bought 4t/5t for my child who will be 4 years old soon. Boxer shorts are marked with size 110, which corresponds to 5T in European sizes. After washing and drying, they fit him perfectly. Definitely not an American 5t, my boy still fits 2t/3t pants at the waist, 4t pants are huge. I would say order at least 1 size up or if in between. He loves her and has no claims. My boy is very slim and without a priest. They should fit him for at least a year. I just needed something to replace the little 3t he had. Paying tons for underwear is never fun, but I'm happy when he's happy. Some are softer than others, but none of them "scratch".
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