President Donald Trump says it’s “ridiculous” that Time named climate activist Greta Thunberg as its Person of the Year. He’s taking aim at the 16-year-old Swede in a tweet. He says she “must work on her Anger Management problem, then go to a good old fashioned movie with a friend!” And he advises, “Chill Greta, Chill!” In response, Thunberg has changed her Twitter profile biography. It now describers her as “A teenager working on her anger management problem. Currently chilling and watching a good old fashioned movie with a friend.” She’s become the face of a new generation of environmental activists, drawing large crowds at protests and conferences.