I bought a 2-4T for my little one who just turned 3 years old. She is of average height and weight and the pants fit perfectly. They are stretchy, comfortable and very thick. My daughter is so comfortable in them that she wears them all day even when she comes home and refuses to take them off. I have since bought two other brands but this is the best in terms of thickness, quality and fit. And contrary to some of the reviews I've seen here, luckily we didn't smell any.
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