Svante Thunberg revealed how his teen daughter, who initiated a global movement demanding world leaders take action over climate change, was crippled with depression and her activism has now made her 'very happy'.
Greta Thunberg may have become the new global climate icon, but the 16-year-old Swedish teenager struggled with depression for three to four years and received no support from her father for skipping school for activism, a bold decision that has inspired millions to join her in raising awareness on environmental issues.
In an interview to the BBC, Greta's father Svante Thunberg said he thought it was "a bad idea" for his daughter to take to the "front line" of the battle against climate change.
Svante said he was "not supportive" of his daughter skipping school for the climate strike.
He said his daughter had struggled with depression for "three or four years" before she began her school strike.
"She stopped talking... she stopped going to school," he said, adding that it was the "ultimate nightmare for a parent" when Greta began refusing to eat.
To help her get better, Thunberg spent more time with Greta and her younger sister, Beata, at their home in Sweden. Greta's mother, opera singer and former Eurovision Song Contest participant Malena Ernman, cancelled contracts so the whole family could be together.
Over the next few years they began discussing and researching climate change, with Greta becoming increasingly passionate about tackling the issue.
"I did all these things, I knew they were the right thing to do... but I didn't do it to save the climate, I did it to save my child," Thunberg told presenter Mishal Husain in Sweden.
He said Greta has "changed" and become "very happy" as a result of her activism.
"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," he said.
"She dances around, she laughs a lot, we have a lot of fun -- and she's in a very good place," he added.
As part of the same broadcast, guest-edited by Greta for Radio 4's Today programme, renowned naturalist and broadcaster David Attenborough told her she had "woken up the world" to climate change and "achieved things that many of us who have been working on the issue for 20 years have failed to do".
Greta was nominated for this year's Nobel Peace Prize, after spearheading a global movement demanding world leaders take action over climate change. It led to co-ordinated school strikes across the globe.
Greta was also named the TIME magazine's 2019 Person of the Year.
However, since her school strike stunt went viral online, Thunberg said she has faced abuse from people who "don't want to change" their lifestyles in order to save the environment.
Earlier this month, US President Donald Trump took a dig at Greta, saying she should "work on her anger management problem".
"Greta must work on her anger management problem, then go to a good old fashioned movie with a friend! Chill Greta, Chill," he said after her combative speech at the UN where she accused the world leaders of inaction on climate change and putting the future generations at risk.