I bought a size 12 for my 12 year old daughter (who is slightly above average at 4ft 11" and 80lbs). Although the pants are thick and have very comfortable material inside, she didn't wear them because her waist is too high (she has to tuck them in to keep them from falling) and the crotch area is too low. They may be suitable for a 12 year old who is taller and heavier than average but in my daughter's case they are not ideal.
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