The Duke and Duchess of Cambridge made a joint appearance with Prince Harry in London on Monday, to mark World Mental Health Day.
The royal trio started the day at event for their Heads Together campaign, which raises awareness of mental wellbeing, at the capital's County Hall.
They took to the stage to speak about providing support for those with mental health challenges, while Prince Harry announced that Heads Together will be the charity partner for the 2017 Virgin Money Marathon.
"We want as many London Marathon runners as possible, spectators around the course and people watching at home to get involved and make it a marathon for mental health," Harry said.
"All of us have mental health. So the more we all get behind this topic, the more we can help not just the individuals suffering, but also their entire families and work colleagues as well. Together we will break the stigma forever and save lives."
Kate, who wore a rose print dress by Kate Spade, expressed her hope for the campaign to "shine a spotlight on emotional wellbeing."
Following their speeches, the royals met with guests who have received help with mental health issues and spoke to different charities which have supported many people in the UK.
The engagements continued with a visit to the London Eye on Monday afternoon, which will be lit up purple in support of the campaign's efforts to end the stigma surrounding mental health.
The Daily Mail reports Kate was given a posy of flowers by 17-year-old Joanne Sibly, who had been chosen to represent Merlin's Magic Wand, a charity which grants wishes to children who are sick, bereaved or terminally ill.