T.L.
Nope next size up is a 6-8. I would purchase one package and see if they fit him. You don't want them to tight or they will rub causing more issues. If the 6-8 are too big you may have to try a different style. You can do the tidy whities, boxer brief or boxers. At our house all my boys (hubby included) wear boxer briefs during the day and boxers at night.