Hi,How old is your son?Is he 15 or younger?Sounds like colitis.That is an infection of the colon.The mouth sores,and the throat,that is some times a part of colitis.You need to have your son,looked at pronto.He needs anyibiotics if it is colitis.Good Luck.Raven33
Hopefully you have seen a pediatriatian by now. I wouldn't wait around for an answer to this, I would get in to see a doctor.