While the Queen Mother gave birth to Queen Elizabeth in April, public celebrations for her birthday do not take place until June and the date changes every year.
So, why does she have two birthdays and when are they celebrated this year? This is what you need to know.
When was the Queen born?
Queen Elizabeth II was born on 21 April, 1926 - the first born child of King George VI and his wife, the Queen Mother Elizabeth Bowes-Lyon.
Her younger sister, Princess Margaret, was born in August 1930.
The Queen is officially the oldest UK monarch in history. On December 20, 2007 she overtook a record set by her great great grandmother, Queen Victoria.
On 6 February 1952, she acceded to the throne after the sudden and untimely death of her father. She was only 25 years old.
On 9 September 2015, she became the longest-reigning English monarch in history. Queen Elizabeth will celebrate 70 years on the throne next year, Queen Victoria reigned for 64 years.
When is her birthday celebrated?
While the queen celebrated her official birthday on 21 April, Trooping the Colour - the name given to the queen’s public celebratory parade - does not take place until June 12.
In April, she had a private family affair, following the death of her husband, Prince Philip.
For the first time since her reign, the gun salutes did not take place in 2020 as she was keen that there would be no special measures which would go against government coronavirus restrictions.
The June parade - which usually attracts thousands of well-wishers to central London - takes place on a Saturday every year, so there is no specific date.
Why does she have two birthdays?
Queen Elizabeth’s birthday parade takes place in June, as Britain has unpredictable weather.
The tradition dates back to the 1700s, when George II in 1748 decided it would be too cold to have the Trooping the Colour parade on his actual birthday - in November.
King George decided to combine his birthday celebration with an annual military parade, in June.
What is ‘Trooping the Colour’?
The Trooping of Colour has marked the official birthday of the British Sovereign for over 260 years.
According to the Royal Household website, over 1400 parading soldiers, 200 horses and 400 musicians put on a display of great military precision and fanfare to celebrate the monarch.
The public line the streets with British flags and other flag-dawning memorabilia, as the parade moves from Buckingham Palace and down The Mall to Horse Guards Parade, alongside Members of the Royal Family on horseback and in carriages.
The display closes with an RAF fly-past, watched by Members of the Royal Family from Buckingham Palace balcony.
The Queen will attend the celebrations and used to attend on horseback herself, to inspect the soldiers in their ceremonial uniform of red tunics and bearskin hats. However, in recent years she has attended by travelling in a carriage.
Will it go ahead this year?
This year, Buckingham Palace has announced that the event will be cancelled for the second year in a row, due to the coronavirus pandemic.
In March, the palace released a statement which read: "Following consultation with Government and other relevant parties it has been agreed that The Queen’s Official Birthday Parade, also known as Trooping the Colour, will not go ahead this year in its traditional form in central London. Options for an alternative Parade, in the quadrangle at Windsor Castle, are being considered."
The statement also confirmed that the annual Garter service, which usually takes place in June, "will not take place this year."
The main change from last year’s scaled down affair is that the queen will be accompanied by her cousin, the Duke of Kent.
In 2020, a “mini Trooping” was staged at Windsor, for the Queen and Prince Philip to attend.
Is the Queen’s birthday a public holiday?
The Queen’s birthday is not a bank holiday and most businesses and services operate as normal on the day of her birthday parade.
Her April birthday is also not a bank holiday, as she celebrates this privately.
When will the Queen’s birthday honours list be announced?
The Queen’s birthday honours list is expected to be announced on her official birthday, this Saturdy (12 June).
Among those expected to receive an award, England footballers Raheem Stirling and Jordan Henderson are thought to be in the running for an MBE.