First off, having a son when you had a stutter isn’t evil like the other commenter said. Your son is still in the developmental stuttering age. He’s 5, so his speech and language skills are still very much developing. There’s a chance it could wear off, but given what you’re saying I wouldn’t expect that. Given his age I’d get him in speech therapy for sure. The upside to all of this is your experience. You can help him cope and get through it, because you have the emotional experience of it as a kid.