Former child actor Raphaël Coleman has died suddenly at the age of 25.

Raphaël was best known for playing Eric Brown in the family comedy Nanny McPhee, a role he filmed when he was 10 years old.

In more recent years, Raphaël had stopped acting, instead devoting his life to activism, as a prominent member of the climate change protest group Extinction Rebellion.

His mum confirmed the news that he had died, sharing a link on Twitter to a piece he had written about the cause.

“Rest in peace my beloved son Raphael Coleman, aka Iggy Fox,” she wrote. “He died doing what he loved, working for the noblest cause of all. His family could not be prouder.

“Let’s celebrate all he achieved in his short life and cherish his legacy.”

His stepfather, Carsten Jensen, wrote in a Facebook post that Raphaël had “collapsed without prior health problems”.

“Death turned off raph,” he wrote. “But it did not turn off the light that burned in him, because no one who has known him has been unaffected by it or will forget it, and that is how he lives on.”

He continued: “When I think of Raph, I see something that will never die, a blunt of eternity, a light beam that lives forever in young people.

“We believe that it is us, the older generations who have something to give the young people. We believe that we are the ones who pass the baton of life to them. But I think it’s the other way around. The young people remind us why we’re alive. They remind us of the purpose of life that this is the gift we must not in distraction until we have unpacked it.”

In addition to his role in Nanny McPhee, Raphaël went on to star in a handful of films released in 2009, including the sci-fi thriller The Fourth Kind, opposite Milla Jovovich, and the horror film It’s Alive.