To go along with what Kaitlin is saying, also check the heel drop in his shoes. We should all be in shoes that are pretty flat from heel to forefoot. Say no to flip flops as well. I know with my 9 year old, he complained of some mild heel/ankle pain about 6 months ago. I switched him to a lower heeled shoe and he quit talking about it. Its funny when he wears the old ones to go play in the woods he will complain about how high the heel feels.