Children to develop at different times. My son was the same way as well until he was 12 years old. Then somewhere around 13 years of age.. he changed.. So it really depends upon when his body gets into puberty. 10 years of age is a bit young yet with a few more years to go. Since this bothers him as well, you may want to talk to the School, perhaps he can be dismissed from Gym class a bit sooner or have a different class all together. Also, you may want to ask him if he would like to follow up with a doctor (just to make sure there is nothing physical at this point) But for him to be and stay little.. at this point, I would say is just needing some time. Now if you want to take this on a medical side, you could talk with a pediatric urologist which may be able to give you more in sight. Since he's already confided in you, then it appears you both have a good relationship, so ask how he would like to pursue this..

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