LONDON – Britain’s Queen Elizabeth II is celebrating s her 91st birthday, in a notably more low-key affair after a year of festivities to mark her hitting 90.

Buckingham Palace shared a photo of the Queen as a baby to mark her 91st birthday on Friday, amid online tributes and military salutes mark the occasion.

She is the world’s oldest reigning monarch as well as Britain’s longest-lived.

Two birthdays

The Queen also celebrates an “official birthday” which falls on the second Saturday in June.

It will be marked with a parade in London known as the Trooping the Colour ceremony – this year’s takes place on 10 June.

Two days earlier, the snap general election announced for Thursday 8 June will be the 17th of the Queen’s reign.

The Queen typically spends her actual birthday privately, but the occasion is marked publicly by gun salutes in central London at midday.

There will be a 41-gun salute in Hyde Park, a 21-gun salute in Windsor Great Park and a 62-gun salute at the Tower of London, the BBC reports.

Reforming the royals

The Queen has remained quiet about political issues including the divisive Brexit referendum and, in January, Prime Minister Theresa May’s controversial decision to invite US President Donald Trump for a state visit.

In modernising her family’s image and refusing to become political, the Queen has held on to the nation’s affection. While generally in good health, she suffered a cold over Christmas and her recovery was watched anxiously.

She has begun handing over duties to other royals, standing down as patron of 25 bodies at the end of last year, including the Wimbledon tennis championships.

While her eldest child Prince Charles is heir to the throne, greater attention has fallen on his two sons William and Harry, who have taken on some of the Queen’s duties.

The arrival of Prince William and his wife Kate’s two children – Prince George and Princess Charlotte – has cemented the country’s positive view of the royal family.

World’s oldest reigning monarch

Elizabeth II (Elizabeth Alexandra Mary Windsor) was born on 21 April 1926 in London. She is the eldest child of the Duke and Duchess of York, later King George VI and Queen Elizabeth, and she was educated privately at home.

In 1947, she married Philip, Duke of Edinburgh, a former prince of Greece and Denmark, with whom she has four children: Charles, Prince of Wales; Anne, Princess Royal; Prince Andrew, Duke of York; and Prince Edward, Earl of Wessex.

She has been Queen of the United Kingdom, Canada, Australia, and New Zealand since 6 February 1952. She is Head of the Commonwealth and Queen of 12 countries that have become independent since her accession: Jamaica, Barbados, the Bahamas, Grenada, Papua New Guinea, Solomon Islands, Tuvalu, Saint Lucia, Saint Vincent and the Grenadines, Belize, Antigua and Barbuda, and Saint Kitts and Nevis.

In 2015, she surpassed the reign of her great-great-grandmother, Queen Victoria, to become the longest-reigning British monarch and the longest-reigning queen regnant and female head of state in world history.

In October 2016, she became the longest currently reigning monarch and head of state following the death of King Bhumibol Adulyadej of Thailand.

In 2017 she became the first British monarch to commemorate a Sapphire Jubilee.

Elizabeth has occasionally faced republican sentiments and press criticism of the royal family; however, support for the monarchy remains high, as does her personal popularity.