Kate Middleton and Prince William are celebrating with volunteers of a special crisis text line on Tuesday.

Six months since the launch of Shout, which offers free and confidential mental health support via text, William and Kate — in a jacket by Smythe and trousers by Joseph — wanted to honor those who have come forward to staff the service. The occasion also provides a chance for those volunteers, who usually work from home, to meet their colleagues across the groundbreaking network that has started to have a real impact on those facing mental health challenges.

Around 600 conversations take place through the service each day. Three-quarters of those who contact Shout are under 25, and the most frequent subjects raised in those conversations are suicide (37%), depression (36%), relationships (29%), anxiety (31%), isolation (19%) and self-harm (17%), the service says.

During the visit, William and Kate spoke with the father of Molly Russell, a 14-year-old who died by suicide in 2017 after viewing graphic self-harm content on social media.

“This is one of the most positive crisis services I have come across,” said Ian Russell, noting that the text-based service is especially appealing to teenagers.

“Support from all ends helps; support from the royal family perhaps particularly helps,” he added.

William and Kate’s outing comes as the organization unveiled a new PSA to encourage even more people to use the Shout 85258 service in the U.K.

Prince William and Catherine Duchess of Cambridge
Credit: Beretta/Sims/Shutterstock

The 24/7 text support service was launched earlier this year by William and Kate alongside Prince Harry and Meghan Markle, as it is a legacy of the royals’ successful Heads Together campaign. Since it kicked off in May, Shout has had 145,000 conversations.

Catherine, Duchess of Cambridge arrives at Shout's Crisis Volunteer celebration event at Troubadour White City Theatre on Novem
Credit: Chris Jackson/Getty Images

Following the initial appeal, 13,000 people registered an interest with Shout and 3,000 enrolled in training. The service now has 1,500 Crisis Volunteers active on the platform with more training, graduating and joining the platform each week.

“We know that we can support more people and this is an opportunity to thank those who have volunteered and to get the message out there for those who are in crisis to text Shout 85258,” a spokeswoman says.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge
Credit: Shutterstock

While Meghan and Harry were not at the event in London on Tuesday, they “continue to be supporters of the service,” a source adds.

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Shout is modeled after — and is a partner of — the American-based Crisis Text Line. Founder Nancy Lublin spoke at the event attended by Prince William and Princess Kate on Tuesday.

Crisis Text Line provides free support 24/7. Text STRENGTH to 741741 in the U.S. to be connected to a crisis counselor.