Last month, Harvey and his mum, Katie Price, won praise for their BBC documentary Katie Price: Harvey & Me, which followed the 18-year-old as he searched for a residential college where he can live now he is an adult.
On Wednesday, it was revealed that he would be working with Mencap, saying he hopes he can be a voice for “young people like me”.
Harvey – who has partially blind and has Prader-Willi syndrome, autism and other learning and behavioural difficulties – explained: “I am so happy to be a Mencap ambassador.
“I want to do good things with the charity like stop online trolling and be a voice for young people like me. I can’t wait!”
Katie also said: “Now Harvey is 18, he is becoming a man and growing in confidence and independence.
“It has been Harvey’s dream to be a role model to young people with complex needs across the UK, and to use his profile to raise awareness. I am thrilled that Harvey has become an ambassador for Mencap.”
She added: “Mencap does fantastic work campaigning against inequalities, supporting people to live the lives they want to and bringing about change in attitudes towards people like my son.
“I am so proud to see him take on this role and I can’t wait to see what he will achieve with Mencap.”
It was recently revealed that Harvey, whose love of trains was featured in the Harvey & Me documentary, had been made a dream offer to do announcements for Network Rail when it’s safe for him to do so.