My friend and fellow Pan Fan on this forum Hannah Rafael-Grippo sent me this article about a young actor named Noah Matthews Matofsky who plays Slightly, the leader of the Lost Boys and Lost Girls, in Peter Pan and Wendy and he’s the first actor with Down syndrome to be cast in a major role in a Disney film!
https://www.dailymail.co.uk/tvshowbiz/article-11971239/Peter-Pan-star-actor-Downs-syndrome-land-major-role-Disney-film.html?ito=native_share_article-nativemenubutton
You can see him in the first trailer among the other Lost Children when Wendy sees them for the first time, and in the featurette you can see him in a behind-the-scenes shot laughing with the actors playing Wendy and John Darling.