there is an experiment where researchers took children and forced them to believe that they stutter, made them read books and then told them that they stuttered a lot, after which they told children to stop stuttering. the researchers did this because they thought stuttering happened because the parents judged the child and told them to stop stuttering. (In the end, these children were never stutterers and never became stutterers, proving that if the person was not born with a stutter, it will not be simple things that will make them stutter!.