Swedish teenage climate activist Greta Thunberg was “slowly disappearing into some kind of darkness” as she struggled with autism in her pre-teen years, according to a new book written by her mother.

Malena Ernman details her 17-year-old daughter’s early life in a revealing new book, Our House is on Fire: Scenes of a Family and a Planet in Crisis (Penguin Books). Excerpts are circulating now before the book’s March publication.

Credited to the family, the book describes Greta’s selective mutism, an eating disorder and her autism diagnosis.

“She stopped playing the piano. She stopped laughing. She stopped talking. And she stopped eating,” Ernman said.

At age 11, Greta’s depression grew and she didn’t speak and wouldn’t eat beyond small amounts of rice, avocado and gnocchi. She was hospitalized for severe weight loss.

“Greta was 11, had just started fifth grade, and was not doing well. She cried at night when she should be sleeping. She cried on her way to school. She cried in her classes and during her breaks, and the teachers called home almost every day. Svante had to run off and bring her home to Moses, our golden retriever. She sat with him for hours, petting him and stroking his fur. She was slowly disappearing into some kind of darkness and little by little, bit by bit, she seemed to stop functioning. She stopped playing the piano. She stopped laughing. She stopped talking. And she stopped eating.”

Bullied at school, she was eventually diagnosed with “high-functioning” autism (Asperger’s) and an obsessive-compulsive disorder.

But the turnaround began when her school showed a film about pollution in the ocean.

Greta was overwhelmed by its message. “She saw what the rest of us did not want to see. It was as if she could see our CO2 emissions with her naked eye,” the book claims.

Time’s Person of the Year for 2019, Greta Thunberg now travels the world advocating for climate awareness and action