I’ll preface by saying I have a moderate stutter, so when my son started stuttering at around 2.5 years old, we immediately got him into speech therapy. Thankfully he grew out of it and stopped stuttering by about 3.5 years old or so. Now he’s 10 and still speaks without stuttering. I was definitely worried that genetics would saddle him with a stutter, thankfully that was not the case at least for now.