The announcement was made today.

Kensington Palace has confirmed that the Duchess of Cambridge will appear alongside her husband, the Duke of Cambridge, and Prince Harry at a reception for World Mental Health Day on October 10th. The event is due to take place at Buckingham Palace on Tuesday, the 10th of next month, and it "will celebrate the contribution of those working in the mental health sector across the UK".

The Duke and Duchess of Cambridge and Prince Harry will attend a reception at Buckingham Palace on World Mental Health Day. pic.twitter.com/P7GLzF8l6V

— Kensington Palace (@KensingtonRoyal) September 20, 2017

Kate, William, and Harry have been advocates of mental health in recent years and this will give them a platform to thank all those who have worked tirelessly to raise awareness. This will mark the 36-year-old's first public appearance since her third pregnancy was announced by Kensington Palace earlier this month. It's thought that the news was made public earlier than expected because Kate was forced to cancel an engagement as she was unwell. According to reports, the Duchess has again been suffering from Hyperemesis Gravidarum, a condition that causes extreme morning sickness and one she suffered from when pregnant with both Prince George and Princess Charlotte.