I went into therapy, a 3 day course to learn how to be in control of my speech but all that did was to give me the tools to learn how to speak in control and the rest is up to you Why I am saying this whatever your son MUST really want it himself, I realise your on here because you love and care about him, but whatever he does whatever therapy he chooses he's got to put in 100% into it its not like learning a trade like brick laying you can not pick it up and put it down whenever he feels like it for the best success he would have to use it every single time he spoke and its tough I'm 15 years down the line and I've no regrets what's so ever Only he can do this if he really wants it I wish him good luck and he's so lucky to have such a supportive mother