You should have your child's feet checked out by a pediatric orthopedist. In many cases, orthotics (custom foot supports) can help relieve pain from flat feet -- which simply means that one or both of his feet don't have a normal arch. But sometimes orthotics (especially the poor-fitting kind sold at the drugstore) can exacerbate foot problems. If the doctor recommends orthotics, he may recommend a podiatrist or brace shop that will have them custom-made for your son to ensure a proper fit as he grows. Some children with flat feet will always need to wear the supports, but other times the orthotics help correct the problem and are only needed for a few years. Be sure to have your son seen by the orthopedist regularly.