Greta Thunberg's father has described how the Swedish climate activist battled depression in the months before she launched school strikes to push for climate action.
In an interview with the BBC, Svante Thunberg said his teenage daughter was hardly speaking to people apart from her family members, and went without eating for months before launching action on climate change.
"I can see Greta is very happy from doing this, and I saw what she was before," he explained.
"I mean, she didn't speak to a single person. She could only eat in her own home. She went on this school strike, and I think day three, someone came along and gave her like a Pad Thai vegan and she ate it. That was like ... I cannot believe I cannot explain that, what a change that meant to her and to us. And it was just like ... she changed and she could do things that she could never have done before.
Thunberg was recently named Time magazine's Person of the Year for 2019. But her father says she's "just like any other kid".
"You think she's not ordinary now because she's special and she's very famous and all these things. But to me, she's now an ordinary child. She can do all the things like other people can. And she's happy. She dances around. She laughs a lot. We have a lot of fun. And she's in a very good place. "
Before the strikes however, she wasn't.
"She fell ill and she stopped talking. She stopped eating and all these things. She stopped going to school. She was basically home for a year. And she didn't eat for three months or two-and-a-half months, which, of course, was the ultimate nightmare as a parent."
On Monday, Greta joined forces with British naturalist and broadcaster David Attenborough to push politicians and businesses to step up action on climate change after a year in which schoolchildren took to the world's streets in protest.
He said he still worries about the "hate" she faces from climate sceptics, but she deals with it "incredibly with it
Svante told the BBC at first, he didn't support his daughter's activism, thinking it was a "bad idea" for her to get on the frontlines. But he and Greta's mother Malena Ernman soon came around, after their daughter called them out on their hypocrisy.
"First, she made a leaflet of, like, I don't know what it's like, lots and lots - 35 facts," Svante said. "And with all the sources to all the facts saw the reports and stuff. And she had those leaflets on the ground. And whenever the journalists came along, she would answer all the questions.
"And that was the surprising thing, because she didn't speak to anyone at the time. She only spoke to me, my wife, her sister and one of her teachers."
He said he still worries about the "hate" she faces from climate sceptics, but she deals with it "incredibly well".