See photos of Queen Elizabeth through the years in honor of her 91st birthday

Future king and queen, George, Duke of York, and Elizabeth, Duchess of York, holding their first child, future Monarch Princess Elizabeth at her christening ceremony in May 1926.Central Press/Getty Images

The young Princess Elizabeth (Queen Elizabeth II) is pictured riding on her tricycle, Circa 1930.Bob Thomas/Popperfoto/Contributor

PHOTOS: Queen Elizabeth II through the yearsAP

Britains Princess Elizabeth leaves Westminster Abbey in London, with her husband, the Duke of Edinburgh, on November 20, 1947, after their wedding ceremony. AP

The Duke of Edinburgh, his wife, Princess Elizabeth and their two children, Prince Charles and Princess Anne, in an official photograph released on January 9, 1951.AP

Queen Elizabeth II is shown in the state coach as she leaves Buckingham Palace for the Houses of Parliament in London on Nov. 4, 1952. AP

Queen Elizabeth II wore the bejeweled Imperial Crown and carried the Orb, in left hand, and Scepter with Cross on June 2, 1953, at the end of the Coronation Ceremony.AP

Queen Elizabeth II, wearing the Imperial Crown, smiles and waves to the crowd from the balcony of Buckingham Palace on June 3, 1953 following her coronation. AP

Britains Queen Elizabeth II and her husband Prince Philip are seen during their visit to the British Virgin Islands, Feb. 23, 1966.AP Photo/ XEP MH

Britains Queen Elizabeth II during the State Opening of Parliament, London, England, in April 1966.AP

Diana, Princess of Wales, left, and Britains Queen Elizabeth II smile to well-wishers outside Clarence House in London, August 4, 1987. AP Photo/ MARTIN CLEAVER

Queen Elizabeth II and her husband the Duke of Edinburgh view the floral tributes to Diana, Princess of Wales, at Londons Buckingham Palace, Friday Sept. 5 1997.AP

Britains Queen Elizabeth II and her husband Prince Philip arrive at a State Banquet for the Commonwealth Heads of Government, in Durban, South Africa, Friday Nov. 12, 1999.AP Photo/ IAN JONES

Britains Queen Elizabeth II at a Sunday church service at St. Mary Magdalene Church in Sandringham, England Sunday, December 24, 2000.AP

Queen Elizabeth II visits the Cloitre des Jacobins monastery, in Toulouse, southwestern France, Wednesday, April 7, 2004. AP

President Barack Obama and Queen Elizabeth II pose for photographers prior to a dinner hosted by the queen, Tuesday, May 24, 2011, at Buckingham Palace in London. AP Photo/ Larry Downing

Queen Elizabeth II leaves after attending a service at St Pauls Cathedral, in central London, Friday, March 13, 2015.AP

Queen Elizabeth II proceeds through the Royal Gallery before the State Opening of Parliament in the House of Lords, at the Palace of Westminster in London Wednesdsay May 27, 2015.Suzanne Plunkett/Pool Photo via AP

Queen Elizabeth II and Prince Philip, the Duke of Edinburgh, walk in the paddock on the second day of Royal Ascot horse racing meet at Ascot, England, June 17, 2015.Alastair Grant/AP

Queen Elizabeth II, right, is presented with flowers as she walks across the Pariser Platz near Berlins landmark Brandenburg Gate, Friday, June 26, 2015.John MacDougall/Pool Photo via AP

Queen Elizabeth II speaks to Prince George as his father Prince William looks on, as they leave after attending the Christening of Princess Charlotte on July 5, 2015.Matt Dunham, Pool, File/AP Photo

Queen Elizabeth II, Prince William and her husband Prince Philip, watch a Royal Air Force flypast from a balcony at Buckingham Palace, in London, Friday, July 10, 2015.Matt Dunham/AP

The Duchess of Cambridge, Chinese President Xi Jinping and Britains Queen Elizabeth II attend a state banquet in Buckingham Palace, London, on Oct. 20, 2015.Dominic Lipinski/Pool Photo via AP

Queen Elizabeth II smiles as she attends the annual Festival of Remembrance with Prince William in London, England, Nov. 7, 2015.Chris Jackson/Pool Photo via AP

Prime Minister of Canada Justin Trudeau meets Britains Queen Elizabeth II during a private audience at Buckingham Palace, London, Wednesday Nov. 25, 2015.Yui Mok/Pool via AP

Queen Elizabeth II reacts with the congregation, during a service of thanks giving and reception at St Columbas Church, in Knightsbridge in London, Thursday, Dec. 3, 2015.

Britains Queen Elizabeth II sits at a desk in Buckingham Palace in London, after recording her Christmas Day broadcast to the Commonwealth, to be broadcast Friday, Dec. 25, 2015.

Queen Elizabeth II waves as she leaves St. Mary Magdalene Church in Sandringham, England, Friday, Dec. 25, 2015.Matt Dunham/AP

Queen Elizabeth II talks to Crossrail workers after she formally unveiled the new Crossrail roundel sign for the Elizabeth Line which will open for passengers from December 2018.Richard Pohle/pool via AP

Britains Queen Elizabeth II leaves after attending the Easter Mattins service at St. Georges Chapel, at Windsor Castle in England, Sunday, March 27, 2016.Kirsty Wigglesworth/AP

Britains Queen Elizabeth II, foreground, rides in a vehicle in Chatham, Kent, England, Thursday Oct. 13, 2016.Gareth Fuller/Pool Photo via AP

Britains Queen Elizabeth II shakes hands with Ambassador of Japan Koji Tsuruoka at Buckingham Palace in central London Thursday Oct. 20, 2016.John Stillwell/AP Photo

Britains Queen Elizabeth II meets members during a visit to the Corps of Royal Engineers at Brompton Barrack in Chatham, Kent, England, Thursday Oct. 13, 2016.Gareth Fuller/AP Photo

Britains Queen Elizabeth II makes a speech as Colombias president Juan Manuel Santos, left, listens during a state banquet at Buckingham Palace in London, Tuesday Nov. 1, 2016Dominic Lipinski/AP Photo

In this photo released early Sunday Dec. 25, 2016, Britains Queen Elizabeth II poses for a photo, sitting at a desk in the Regency Room of Buckingham Palace in London.Yui Mok/AP Photo

Queen Elizabeth II arrives at the Fiji Exhibition at the Sainsbury Centre for Visual Arts at the University of East Anglia, Norwich, eastern England, Friday Jan. 27, 2017.Arthur Edwards/pool via AP

Britains Queen Elizabeth II watches her husband the Duke of Edinburgh feeding a banana to and elephant at the Zoological Society of Londons Whipsnade Zoo.David Rose//Pool Photo via AP

Britains Queen Elizabeth leaves after attending the Easter Sunday service at St Georges Chapel at Windsor Castle in Berkshire, England, Sunday, April 16, 2017Peter Nicholls/Pool Photo via AP

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Thursday, April 21, 2016

Happy Birthday, Queen Elizabeth II! The longest-reigning British monarch turns 91 years old on April 21, 2017.

The queen's birthday is marked twice a year, once when she was born (in April) and once on the "official" birthday in June, when there is a parade.

The royal family celebrated the day on social media by sharing photos of the Queen through the years.

Now the oldest reigning monarch, she dedicated her life to service on her 21st birthday. More > https://t.co/mcVCkOE7UY #QueensBirthday pic.twitter.com/chSdUWfARJ
— The Royal Family (@RoyalFamily) April 21, 2017

To mark The Queen's 91st birthday, we are sharing this photo from 1952 of Her Majesty and The Prince of Wales. #HappyBirthdayHerMajesty pic.twitter.com/ednBFygYue
— Clarence House (@ClarenceHouse) April 21, 2017

Check out the gallery above to see how Queen Elizabeth II has changed from her days as Princess Elizabeth, to ascending the throne in 1952, to today.

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