My son had one when he was born. Doc said to watch it as most go away by the time they are 5 and if it hadnt then we'd need him to have it surgicially corrected. AT 5.5 he still had it, so we had the surgery. The doc said that as they get into elementary school and want to do sports, etc, it could become a problem so that is why they fix them if they are still there at age 5. He's 6 now and you cant even see the scar where he had it done and is totally fine and active.
When I was pregnant with him, MY bellybutton herniated and I had it fixed when he was 3 months old. For me, it was uncomfortable when I coughed or sneezed so I wanted it fixed. It didnt hurt, but was uncomfortable and yucky feeling. Does your son's bother him at all? Did your doc say he should have it corrected if it doesnt go away in a year?
Good luck with your decision.
- X.