Prince William, Kate and Prince Harry set to attend a special Christmas party

By Ainhoa Barcelona

Prince William, Kate and Prince Harry have at least one very special holiday event in their calendars this year, one they absolutely couldn't turn down. Following an annual general meeting on Dec. 19, the royals will be guests of honour at a Heads Together party hosted by youth support service The Mix. The shindig will celebrate the charity's volunteers and counsellors.

Before the party, William and Harry will join a group breakout session where counsellors and volunteers will share knowledge and get training on dealing with a range of issues, with a focus on supporting people who are suicidal and helping young people coping with homelessness. Kate, meanwhile, will join a live online chat about counselling with volunteers and young people from around the UK.

TAP TO VIEW GALLERYWilliam, Kate and Harry will attend a charity Christmas party on 19 December

The Christmas party reception will then follow, and the royals will have a chance to mingle with the volunteers and hear about the life-changing work they do to support young people. They will kick off The Mix Annual Awards by presenting the Volunteer of the Year Award.

DUCHESS KATE'S MANY ROYAL PATRONAGES

The Duke and Duchess of Cambridge and Prince Harry will have received a score of Christmas party invitations this year, and while they can't go to all, they will have wanted to show their support for this cause close to their heart.

The Mix is one of eight charities involved in their royal campaign Heads Together, which aims to change the national conversation around mental health. The charity focuses on supporting young people aged between 13 and 25 through any challenge, from homelessness to finding a job.

The royal trio launched the Heads Together campaign in May

William, Kate and Harry launched the Heads Together campaign in May through their Royal Foundation and in the past they have spoken about the need to end the stigma surrounding mental health.

"Mental health is not a dirty word," William has said. "We all have mental health like we do physical health, good or ill. But not seeking help at those times when it all seems too much, or we are depressed or anxious, can impact the rest of our lives. Put simply, the three of us want to make asking for help no longer a big deal."

The royals will spend Christmas at Sandringham with the Queen

William, Kate and Harry will be getting in the festive spirit. The royals traditionally attend a pre-Christmas lunch at Buckingham Palace, organised by the Queen, the week before Christmas for the whole extended family.

Select members of the family are then invited to Sandringham House to spend Christmas Eve and Christmas Day with Her Majesty and Prince Philip. Guests arrive at the 20,000-acre estate from 23 December in order of precedence, with Prince Charles and the Duchess of Cornwall usually the last to arrive.

Prince William and Kate, and their children Prince George and Princess Charlotte, will also spend part of the Christmas break with Kate's side of the family, the Middletons, in Berkshire.

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