Charlotte offered her arm for the 3-year-old to take to balance herself as she sat up and joined her older sister in dancing.
As the princess helpfully helped her down, Lena then proceeded to start bouncing up and down to the beat.
While not dancing herself, Princess Charlotte could be seen enthusiastically clapping away to the music.
Princess Charlotte stepped in to help out Lena Tindall as she stepped out of her seat
Princess Charlotte showed off her older sister skills by not even turning to help Mia
Prince George and Princess Charlotte joined their parents in the royal box for Saturday night’s Party at the Palace, when the monarch received affectionate tributes from the Prince of Wales and national figures – and had tea with Paddington Bear.
The Cambridge trio also made their official Trooping the Colour debut on Thursday as they travelled to the service as part of the open carriage procession to Horse Guards Parade.
They observed from a building overlooking the parade as their father and grandfather took the salute from the Irish Guards on behalf of the Queen.
George and Charlotte also joined their parents in Wales on Saturday as part of the Jubilee celebrations.
Ahead of the pageant, Camilla, the Duchess of Cornwall joined Charles at a flagship feast at The Oval cricket ground in south London.
The Earl and Countess of Wessex met with people creating the “Long Table” down on The Long Walk leading up to Windsor Castle.
During the event, Charles said he hoped the nation does not return to “bickering” after the feeling of “togetherness” over the Platinum Jubilee weekend.
Some 10,000 people including a cast of 6,000 performers took part in the 3km carnival procession from Horse Guards, along Whitehall to Admiralty Arch, and down The Mall to Buckingham Palace.
Several of the Queen’s grandchildren and great-grandchildren joined the celebrations
The pageant marked the final day of the four-day weekend celebrations to mark the Queen’s 70th year on the throne.
Her Majesty attended Trooping the Colour on Saturday, taking the salute as troops headed back towards Buckingham Palace from Horse Guards.
But she was forced to shelve plans to attend a thanksgiving service at St Paul’s Cathedral after suffering “discomfort” during her balcony appearance.
Source: EXPRESS CO UK