Stuttering starts at various ages. It usually begins in young children, but sometimes doesn't start until the teen years or adulthood. I wonder if this is because, for those prone to stutter, they had a relaxed childhood with parents and/or caregivers who had no reaction to the first time their child stuttered. Since stress makes stuttering worse, having a parent react with an "Oh, no! We must fix that" attitude as well as the expression of horror every time their child bumbled while speaking would make the child more sensitive to differences in speech.
Not only do parents of young children need to be informed how to react to their child, but it would be helpful if the entire population understood stuttering and what to do when talking with someone who stutters.
Click on the title of this post to see a chapter from the book "To the Pediatrition" that encourages Pediatritions to counsel parents on their reactions to stuttering moments in their child. If parents of young children get help "before the child has developed a serious social and emotional response to stuttering, prognosis for recovery is good."