The royal trio are set to take part in a documentary for the BBC leading up to the London Marathon in April, according to reports Friday.
The royals are working with presenter Nick Knowles, who told The Sun, “I’m working on a mental health documentary with the young royals, which should come out around the time of the marathon. I can’t tell you anymore.”
Knowles also worked with William and Harry on the day that they helped renovate homes for injured or sick Armed Forces members on the BBC show DIYSOS in September 2015.
The royals’ Heads Together campaign is the charity partner of the London Marathon in April, and beneficiaries and members of the mental health charities that come under its umbrella are set to run that day.
Next Tuesday, William, Kate and Harry will speak at a briefing to give an update on the campaign and urge people to continue the conversation about mental health – “with a friend, family member, colleague, or a professional when dealing with a mental health challenge.”
This week, they were praised by a leading mental health expert for their role in bringing the issue forward. Professor Peter Fonagy, chief executive of the charity Anna Freud National Centre for Children and Families, told PEOPLE that politicians wouldn’t be as open about tackling the issue had it not been for Kate, William and Harry.
“I don’t think the Prime Minister would be where she is if it wasn’t for the royal family’s Heads Together program, which I think was the brainchild of Her Royal Highness,” he said. “She has caused a national shift in terms of the acceptability of mental health as a problem that we all needed to deal with.”
The royals’ office at Kensington Palace and the BBC had no comment on the documentary.