Rachel Riley often voices her support for various charities and initiatives on Twitter – and her latest post was no different.MORE: Rachel Riley has the cutest interaction with daughter Maven ahead of family milestoneTaking to her social media account on Friday, the Countdown host - who is a doting mother to two young daughters - revealed her friend John reached out and asked her to help raise the awareness of avoidant/restrictive food intake disorder (ARFID) after his son Arthur was diagnosed with it.WATCH: Rachel Riley shares rare video of daughter Maven chatting"An old friend just got in touch after a long struggle to get a diagnosis for his son with avoidant/restrictive food intake disorder (ARFID)," she shared alongside a link to her friend's charity page.MORE: Rachel Riley shares new candid picture of Pasha Kovalev and baby Noa - but fans question one detailREAD: Rachel Riley reflects on heartache of suffering a miscarriage last year"He wants to spread the word so other families won’t have the same struggle. Big love to little Arthur and fam [blue heart emoji]."ARFID is a new diagnosis and was previously referred to as Selective Eating Disorder.