M.R.
My son, who is the 3rd child, went through this in Kindergarten. I did not really notice it but his teacher did and recommended him for speech therapy through the school. All the research that I did showed not to say "Stop" but to stop what you are doing and get to their level and show that you are listening to what they have to say. If you bring negative attention to the stuttering it creates a stress for the child and perpetuates the stuttering. My son was trying to get his thoughts out too fast. His brain was going faster than his mouth and he wanted to get everything out before a sibling or friend would interupt him. We had a family meeting and talked about not talking over each other and to let each other finish their thoughts before anyone else could talk. The speech therapist did give him some relaxation techniques and told me to prompt him to get his thoughts together. It is very important to not make them feel self conscious about it. My son is now 10 and has not stuttered since 2nd grade.