Help! Son must not have access to child trust fund

[Comingup]

My son will be 18 soon and is addicted to weed, he is aggressive and abusive. Can anyone tell me what actually happens when18th birthday comes up? Do they write to the child? Can I stop it from maturing or whatever it does. I am really panicking as I have had a massive altercation with him where he admits spending a fortune every week on weed. I plan to ring the company but after tonight don't think I will sleep at the thought of him having any more money to harm himself with.

@Comingup I’ve found that teens talk.

My ASD/ADHD teen who also, sadly, blows all his money on pot asked me about his child trust fund on his 18th birthday. His friends who had hit 18 first had told him about it. I’m still hanging onto the details for now and telling him in a few years it could be worth double and be towards a deposit on a flat. Not a lot else I can do but hope for the best.

As he’s still under age can you go to the dr about his drug habit? I would speak to a solicitor and see what, if anything you can do.