My son developed a stutter round the same age , it disappeared within a couple of years he is now 12 and doesn't even remember it .. We never pointed it out and I think it was the best approach. I had a severe stutter until my mid 20s , I couldn't even walk into a shop and ask for phone credit , I spent years going to speech therapy and I can honestly say I never used one of the techniques they thought me , for me it was useless. Hopefully your child grows out of it but if you make a big deal of it that is less likely, imo .