From the Princess of Wales' supportive hand on her eldest son, Prince George's back to Kate sharing a giggle with King Charles, there were plenty of heartwarming moments from today's Trooping the Colour.Whilst the number of royals on the Buckingham Palace balcony for the monarch's official birthday celebrations has decreased from 44 to 14 amid His Majesty's slimmed-down approach, there's still plenty of opportunity for the Firm's members to put on a charming display.Some of today's highlights include Prince Louis playfully reacting as he watched the acrobatic Red Arrows flying overhead and Catherine pictured happily chatting away with Prince George, 12, and Princess Charlotte, 11, during the carriage ride to Horse Guards Parade.One photo showed Catherine looking lovingly at the Prince of Wales as they stood on the balcony after William joined the royal procession on horseback alongside the Princess Royal and the Duke of Edinburgh.Elsewhere, the royals were filmed laughing and sharing jokes with each other in rare behind-the-scenes footage from the day, shared by the King and Queen and the Prince and Princess of Wales. The Princess of Wales comforts Prince Louis during the carriage ride in London today Kate leans forward to talk to her children during the Buckingham Palace balcony appearance The Princess of Wales placed her hand on eldest son's back as they walked off the Buckingham Palace balcony The King exchanged a smile with his daughter-in-law King Charles led a slimmed-down contingent of senior royals, including Queen Camilla and the Prince and Princess of Wales, on the Buckingham Palace balcony as London was painted red, white and royal blue to mark the monarch's official birthday. Shortly after the spectacular Red Arrows flypast rounded out the celebrations, Prince William and Catherine shared an intimate video of the family laughing and larking about to mark the joyous occasion on Instagram. Earlier in the day, the royals attended the monarch's official birthday at Horse Guards Parade in London as throngs of fans flocked to The Mall to witness the stunning display of military pomp and pageantry.Kate, 44, putting on a typically elegant display in a Catherine Walker light blue and white coat dress and a matching Philip Treacy hat, was sat next to her youngest Louis, eight, when travelling in the royal carriage procession.Charlotte, 11, and George, 12, looking smart in a suit and a tie that matched his mother's ensemble, were placed opposite the pair in the open-top coach.The King, meanwhile, wore his military uniform, with Queen Camilla wearing a red silk crepe Grenadier Guards uniform dress, designed by Fiona Clare, as the two travelled from Buckingham Palace to the parade grounds.It was a family affair for the Firm as the Prince of Wales rode on horseback while wearing the Full Ceremonial Order of the Welsh Guards. He was accompanied by the Duke of Edinburgh and the Princess Royal as they flashed a salute on their way to Buckingham Palace. Prince Louis, who has come to be known for his cheeky antics at royal events, put on a very animated display on the Buckingham Palace balcony at Trooping the Colour today Prince Louis, eight, and Princess Charlotte, 11, were spotted peeking out the window before heading on the balcony at Trooping the Colour today The Duke of Kent sat near the young royals before appearing on the balcony at today's Trooping the Colour Members of the Royal Family on the balcony of Buckingham Palace, London, to view the flypast Prince Louis adjusts his tie while watching the Trooping the Colour celebrations in London Prince George and Prince Louis attend the Trooping the Colour celebrations The King and Queen attended the birthday parade, riding in a carriage during the event Future heir to the throne George exchanging a smile with the Princess of Wales The Princess of Wales and her children waved to the crowd while on the palace balcony Prince George shares a giggle with his mother, the Princess of Wales, and his sister, Princess CharlotteHighlighting the strong bond between Kate and her children, they were all dressed in complementary outfits - from George and Louis's ties that were the exact shade of Kate's dress to Charlotte's printed cream dress with hints of blue.Known for his cheeky antics, Louis flashed his gap-toothed smile at the crowds that eagerly held up their phones to try to snap a picture of the Royal Family during a spectacular display of military pomp and regalia.The future heir to the throne, George, 12, was confident as he waved at well-wishers while seemingly joking and chatting with his younger sister, Charlotte.Guardsmen in their scarlet tunics and bearskin caps delivered a display of precision marching on Horse Guards Parade, honed over weeks of practice and part of their ceremonial duties when not fighting soldiers.The national celebration is one of the highlights of the royal calendar and will later feature the Royal Family assembled on Buckingham Palace's balcony for the traditional flypast of RAF aircraft.The colour – regimental flag – trooped this year was the King's Colour of the Grenadier Guards.Charles presented the new colour to the regiment during a ceremony in the gardens of Buckingham Palace on June 9. Kate's look of love for William as they stood on the balcony King Charles and Queen Camilla smiling before they departed for Horse Guards Parade King Charles feeding one of his horses a carrot Princess Charlotte wore a cream dress and a matching bow The Prince of Wales, in full military regalia, with his horse Darby ahead of the monarch's official birthday parade Catherine pictured happily chatting away with Prince George, 12, and Princess Charlotte , 11, during the carriage ride to Horse Guards Parade Kate watching the parade alongside the monarch The Grenadier Guards were raised in 1656 in Bruges, Belgium, by the exiled King Charles II to protect him during the period Oliver Cromwell ruled England.Charles, Colonel-in-Chief of the Grenadier Guards, visited his King's Company at their barracks in Aldershot on the eve of Trooping and wished them 'great success' for the big day.He told the company: 'Since Easter you've been practising rigidly and I can hear from Buckingham Palace the sound of the drums thumping away regularly so I know you're all marching up and down trying to get ready for the parade.'The King went on to say: '…ever since the last 370 years of your existence you have made us all in this country so incredibly proud of your effort, your service and your sacrifice over all those years and I feel very proud and privileged to be here.'The King's Birthday Parade this year comes exactly one week after the royals gathered in Kemble, Gloucestershire, for Peter Phillips and Harriet Sperling's 'intimate' wedding.Catherine looked the picture of poise as she arrived at All Saints Church in a Roland Mouret £750 dress and Jane Taylor hat, alongside her husband William, 43.The future Queen was met with the sounds of cheers from crowds of well-wishers who had gathered to catch a glimpse of the royal guests.Trooping the Colour is a military ceremony that dates back to the 18th century and is one of the most high-profile royal events of the year.It is rooted in battlefield custom, when regimental flags, or 'colours,' were trooped in front of soldiers to ensure they could be recognised amid the smoke of combat.