The youngest members of the Royal family stole the show on the balcony of Buckingham Palace, as they giggled, gasped and waved through a Trooping the Colour flypast.
Prince George and Princess Charlotte joined Savannah and Isla Phillips at the front of the balcony, watched indulgently by the Queen as they larked about in front of the crowds.
Savannah, seven, appeared unimpressed by her cousin Prince George's noises during the national anthem, clamping her hand firmly over his mouth to keep him quiet.
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Princess Charlotte, three, beat time with the familiar song on the balcony, while older members of the family stood in silence.
The Duchess of Sussex, making her first appearance for Trooping the Colour, appeared to be listening carefully to her husband of three weeks, as he talked her through what to expect from the dramatic RAF flypast.
The Queen beamed at the sight of the Red Arrows, which turned the London sky red, white and blue for the cheering crowds.
Celebrating her official 92nd birthday, she was joined by four generations of her family while the Duke of Edinburgh, who has retired from public duties and turns 97 tomorrow, remained out of sight.
The "balcony moment" at Buckingham Palace marked the biggest public gathering of the Royal family this year, with some of those appearing unable to attend the wedding of Prince Harry and Meghan Markle three weeks ago due to capacity restrictions at St George's Chapel.
Prince George, Princess Charlotte, Isla and Savannah, all clearly excited for their big moment in front of the watching world, were given books explaining the different aircraft flying over their heads, studying them carefully before the noise of the flypast distracted them.
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Then, they concentrated on waving wildly to the pilots, and clapping each new arrival.
Paramedics had to arrive at the celebrations however after Field Marshal Lord Guthrie, the former Chief of the General Staff, was injured after falling from his horse.
Lord Guthrie, 79, was treated on The Mall by paramedics after appearing to collapse and slip from his steed.
He was taken to hospital, where aides said he was "being well looked after".
Lord Guthrie, who was taking part as Colonel of the Life Guards, was Chief of the Defence Staff, the professional head of the British Army, from 1994 to 1997, and Chief of the Defence Staff from 1997 until his retirement in 2001.
Earlier the Duchess of Sussex had arrived for her first Trooping the Colour ceremony, returning from honeymoon to travel in a carriage with her husband.
Meghan experienced the pomp and pageantry of the event for the first time when she arrived on Horse Guards Parade with Harry in a carriage, along with the Queen's cousin the Duke of Kent.
The couple were greeted by the sight of hundreds of Guardsmen in their scarlet tunics and bearskins lined up on the parade ground - Henry VIII's former jousting yard - as the event began.
The Duke and Duchess, who married exactly three weeks today, travelled from Buckingham Palace along the Mall to cheers from royal fans gathered in the famous London thoroughfare.
The Duchess of Cornwall and Duchess of Cambridge were in another carriage while a third carried Princesses Beatrice and Eugenie, the Countess of Wessex and her daughter Lady Louise.
The Duchess of Sussex wore a dress by Carolina Herrera and a hat by Philip Treacy, while Kate wore a dress by Alexander McQueen and a hat by Juliette Botterill.
Camilla wore a pale blue silk dress and coat by Bruce Oldfield and a hat by Philip Treacy.
The Queen soon made her entrance onto Horse Guards in an Ascot Landau after making her journey from her famous London home Buckingham Palace.
The 7,500 guests seated in stands lining the parade ground stood as a mark of respect as the monarch arrived and began inspecting the massed ranks of the troops.
The Duke of Edinburgh, who celebrates his 97th birthday on Sunday, has retired from official public duties and did not attend.
But the Queen was accompanied by the royal colonels, all on horseback: Prince of Wales, Colonel of the Welsh Guards, the Princess Royal, Colonel of the Blues and Royals, and the Duke of Cambridge, Colonel of the Irish Guards.
Also riding in the ceremony for the first time was the Duke of York in his new role as Colonel of the Grenadier Guards.
Among the guests was Defence Secretary Gavin Williamson, the Prime Minister Theresa May normally attends but is at a G7 meeting of world leaders in Canada.
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The massed bands of the Household Division and the Mounted Band of the Household Calvary provided the musical backing for the ceremony.
While also taking part was the King's Troop Royal Horse Artillery, who will fire a 41-gun salute in Green Park to mark the Queen's official birthday.
The colour was first trooped through the ranks of soldiers before the Guardsmen marched past the Queen, first in slow then in quick time.
As the ceremony came to an end, the thousands in the stands were treated to the sight of the Blues and Royals and Life Guards from the Household Cavalry Regiment.
The mounted soldiers and officers in their gleaming breast plates and plumed helmets rode past the Queen with the horses throwing up dust.
From the vantage point of the Duke of Wellington's old office, which overlooks Horse Guards Parade, Camilla, Harry, Meghan and Kate and the other members of the Royal Family watched the finale of the event.
After the ceremony the royal family will head back to Buckingham Palace and gather on the balcony to watch the RAF flypast.
Among the 23 aircraft taking part are modern jets and historic aircraft, while the Red Arrows will be the finale.
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The Queen's actual birthday was on April 21 when she turned 92.
Drum major to mark end of 40-year career
A drum major is poised to parade in his final Trooping the Colour on a day which will also mark the end of his four-decade career in the British Army.
The centuries-old military spectacle of might, splendour and precision marching will take place on Horse Guards Parade this Saturday to mark the Queen's official birthday.
It is an important day in the armed forces' calendar and for the monarchy, where the families and friends of those on parade proudly watch the ceremony.
For Drum Major Steve Staite, who has taken part in Trooping the Colour at least 26 times - 17 as drum major, something the Army claim is a world record - this year's Queen's birthday parade carries extra significance.
"I am very excited to be doing my final Queen's birthday parade, it is a culmination of my career over the four decades," he said. "And what better day to go out on than the Queen's birthday?"
The 55-year-old who is originally from Preston, Lancashire, joined the 1st Battalion Grenadier Guards at the age of 16 on June 19 1979 and was appointed drum major to the Queen in 1995.
"We are personal drummers to her majesty, we get a royal warrant signed to that effect, and it is the greatest honour in the world, you can't beat it," he said.
As one of five drum majors wearing the elaborate gold-thread state clothing, during Trooping the Colour he marches one of the divisions up to Horse Guards to get them on to parade.
Drum Major Staite also leads one of the massed bands during the parade in slow and quick time - something the father-of-two agreed very few people get to do.
"A lot of people tell you it is great to march behind a band, but you can't beat marching in front of it," he said.
During his career Drum Major Staite said he has visited 40 of the 50 states in America, and has worked in Kenya, Northern Ireland, Saudi Arabia, Kuwait and Iraq.
It was during a posting to West Berlin on his first deployment that he also patrolled the Berlin Wall and guarded Adolf Hitler's deputy, Rudolf Hess, when he was held at Spandau prison.
Quizzed on what that experience was like, Drum Major Staite who plans on retiring to Middlesbrough with his wife Fee, said: "You just sat in a sanger at Spandau prison.
"You weren't really allowed to look into the yard, it was just a normal prison with one person in it. But driving around the Berlin wall in those days was something very, very different."
Posted to Household Division headquarters in 2000, he was involved in the funeral of the Queen Mother and Lady Margaret Thatcher, the closing ceremony of the 2012 Olympic Games and the royal weddings of Prince Charles and Prince William.
Guardsman hopes turban marks 'historic change'
A Coldstream Guards soldier who will wear a turban as he parades during Trooping the Colour has said he hopes it is looked upon as a "new change in history".
More than 1,000 soldiers will take part in the ceremony which marks the Queen's official birthday on Saturday as the nation honours the monarch.
For Guardsman Charanpreet Singh Lall the event is not only his first Trooping the Colour, but also marks the first time a member of the Coldstream Guards has taken part wearing a turban.
The 22-year-old from Leicester said: "I hope that people watching, that they will just acknowledge it and that they will look at it as a new change in history.
"I hope that more people like me, not just Sikhs but from other religions and different backgrounds, that they will be encouraged to join the Army."
A member of the 1st Battalion Coldstream Guards, the turban he will be wearing during Trooping the Colour will be black, featuring the ceremonial cap star to match the bearskin hats.
Gdsm Lall who joined the British Army in January 2016, was born in Punjab, India, and moved to the UK as a baby, said he is feeling "quite excited" ahead of the event.
"I'm quite proud and I know that a lot of other people are proud of me as well," he said. "It is a good feeling... there's going to be a lot of eyes and I am going to have an influence on other people."
Trooping the Colour originated from traditional preparations for battle.
Colours, or flags, were carried, or "trooped", down the ranks so they could be seen and recognised by the soldiers.
In the 18th century, guards from the Royal palaces assembled daily on Horse Guards to "troop the colours", and in 1748 it was announced the parade would also mark the Sovereign's official birthday.
This year the ceremony, which is staged every June in London's historic Horse Guards Parade, will see the Colour of the 1st Battalion the Coldstream Guards being trooped.
With weeks of rigorous training under his belt, on the day he and many other soldiers will wear immaculate uniforms and march with precision up the Mall and onto parade.
Gdsm Lall added: "For myself, being the first turban-wearing sikh to troop the colour and to be part of the escort it is a really high honour for myself, and hopefully for everyone else as well."
He revealed his family including his mother, father and sister, who are "really, really proud" of him, will be coming to watch him take part.
"My mum was crying on the day I passed out so I wonder what is going to happen to her when she sees me in this," Gdsm Lall added.
Jay Singh-Sohal, chairman of the WW1 Sikh Memorial, said: “This is a tremendous achievement for a young Guardsman dedicated to his duty, but also an inspiration for our community.
"It’s wonderful to see young Sikhs upholding our warrior traditions, keeping their turban and beard identity as per Khalsa traditions and wearing the Queen’s uniform. I hope many more will serve in this way.”