The royals will be out in force for the annual Commonwealth Day service at Westminster Abbey next week.
The Queen, who is head of the Commonwealth, will be joined by the Prince of Wales, along with the Duchess of Cornwall, the Duke and Duchess of Cambridge, the Duke and Duchess of Sussex and the Duke of York next Monday.
It has a special significance this year, with 2019 marking the 70th anniversary of the modern Commonwealth.
The Commonwealth is a global network of 53 nations and almost 2.4 billion people, a third of the world’s population.
Former Suits star Meghan Markle took part in her first official event with the Queen at last year’s service when she joined the royal family at Westminster Abbey ahead of her wedding to Prince Harry.
Now heavily pregnant Meghan is returning as a mother-to-be.
Charles’s future as the head of the Commonwealth when he becomes king was backed by Commonwealth leaders last year, and Harry and Meghan are taking a lead on Commonwealth Youth Matters.
Highlights of the service will include special musical performances by Grammy-award winning group Clean Bandit and tenor Alfie Boe.
A reflection will be given by Lewis Pugh, an endurance swimmer, ocean advocate and the UN Patron of the Oceans.
The service will be broadcast live on BBC One and across the BBC World Service.
In the evening, Charles and Camilla will be guests of the Commonwealth Secretary-General at the annual reception at Marlborough House.