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"She was slowly disappearing into some kind of darkness and little by little, bit by bit, she seemed to stop functioning," Greta Thunberg's mother has revealed about her daughter's eating disorder.
Malena Ernmam, a Swedish opera singer, and her husband Svante Thunberg, an actor, have written about their daughter's troubled childhood and her rise to becoming the world's most recognized climate change activist in a new book.
In an emotional story, Ernman told of Greta's struggles at age 11, becoming near-mute and battling an eating disorder. Extracts from the book, Our House Is On Fire: Scenes Of A Family And A Planet In Crisis, were published in the Observer.
"She stopped playing the piano. She stopped laughing. She stopped talking. And she stopped eating," Ernman wrote.
She shared the frustrations as their daughter started fading away before their eyes. At first, they calmly asked their daughter to eat. But hopelessness and fear soon took over their patience.
"Eat! You have to eat, don't you understand? You have to eat now, otherwise, you'll die!" Ernman remembered saying.
After two months of not eating, Greta had already lost 10kg. She started taking antidepressants as her parents continued to battle the unforgiving illness.
But they started to make the life-saving process she desperately needed.
Once she began gaining weight, a psychiatrist diagnosed her with Asperger's, "high-functioning" autism, as well as obsessive-compulsive disorder.
But as she went back to school her father found out she was being bullied during a school ceremony where fellow students pointed and laughed at her when she walked past.
A turning point for Greta's illness was her newly-found passion to stand up for climate change after watching a film in class about rubbish in the oceans.
In 2018, she planned her first school climate strike. Her mother described how she "saw what the rest of us did not want to see".
"It was as if she could see CO2 emissions with her naked eye."
Now 17, Greta is an internationally recognised climate change activist and is the face of the youth climate movement. Last year she was named Time magazine person of the year.