Hi Nicola
Welcome to the forum.
You might want to have a look at the following FAQ which explains where everything is;
www.benefitsandwork.co.uk/guides-for-claimants/faq/forum.
Your son should receive the LCWRA in his next assessment period following the assessment phase.
To get accurate advice we would advise you to seek specialist advice from your local Welfare Rights Organisation:
advicelocal.uk where they can take all your circumstances into consideration when giving you advice.
Gary