Tuesday, 21 April, would have been Queen Elizabeth’s 100th birthday.
A number of events are taking place for the Royal Family to remember her and there will also be a global digital memorial allowing people to contribute their personal memories of the life of Britain’s longest-reigning monarch.
The King and Queen Camilla will visit the British Museum to view plans for the Queen Elizabeth II national memorial in St James Park in London designed by architect Sir Norman Foster.
Later in the day, they will host a reception at Buckingham Palace where guests will be presented with birthday cards by the King.
The Princess Royal will honour her mother by officially opening the Queen Elizabeth II Garden in Regent’s Park, London.
Buckingham Palace has also announced that award-winning historian Dr Anna Keay will write the the late monarch’s official authorised biography.
“I am deeply grateful to His Majesty The King for entrusting me with this responsibility and for granting me access to her papers, ” Dr Keay said.
“I will do all I can to do justice to her life and work.”
As well as being given access to her personal and official papers held in the Royal Archives, Dr Keay will also speak to those who knew the late Queen best during her life, including members of the Royal Family.
Queen Elizabeth II: Her Story, Our Century, is on Sunday at 21:00 BST on BBC One and iPlayer