You are too small. My son is 3 years old, I bought a size 6. It is currently sitting very tight on him before washing. He is about 32 pounds and 39-40 inches tall. The size chart lists a range of 45 to 48 lbs. Basically it is false advertising. I recommend buying 2-4 sizes bigger or not. It's difficult to make an exchange if they don't have other sizes available, and it becomes difficult for them with children when we tell them we want to come back after we try them on.
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