I started stuttering around age 6-7, after I had a lisp corrected at speech therapy in school. Stuttering has been shown to have a genetic component, though they're not sure how much. For me, personally, my dad and one of my uncles (from my mom's side) both stuttered as children, with the maternal uncle carrying a mild stutter into adulthood. If your child stutters, whatever you do, don't freak out about it! That will just make them stressed when they have to talk, which could make it worse. As others have mentioned, the vast majority of children outgrow stuttering, so even if your child does stutter, it's likely they won't have it as an adult.