From BBC News:
The 20-year-old has become one of the world’s best-known campaigners against climate change. She first learned about climate change when she was eight. At the age of 11 or 12, she started suffering from depression, according to her father, Svante: “She stopped talking… she stopped going to school,” he said. Around the same time she was diagnosed with Asperger’s syndrome, a form of autism.
In summer 2018, aged 15, Ms Thunberg held the first “School Strike for Climate” outside the Swedish parliament. The protest was widely covered the international media, and hundreds of thousands of young people across the world joined her Fridays For Future strikes. Mr Thunberg says Greta became “much happier” after she started campaigning. She has described her autism diagnosis as a “superpower” which has helped motivate her protests. “Being different is a gift,” she told the BBC. “If I would’ve been like everyone else, I wouldn’t have started this school strike, for instance.”
More here.