Newly 21-year-old Posty fan got the surprise of a lifetime while he was out at his birthday dinner! One Right Now singer Post Malone went out to his favorite sushi restaurant in L.A. when he met Andrew, celebrating his 21st! Posty goes on to introduce himself saying “Hi, I’m Austin,” referring to his legal name, Austin Post. Andrew has autism and his mom Nicole states Andrew knows every single Post Malone song according to People!