The fourth-in-line to the throne exchanged a few words with Zara Tindall who, sitting behind her, helped the child take her seat by moving away from the chair a pillow.
As Queen + Adam Lambert opened the concert by performing their iconic We Will Rock You, the adorable girl was spotted clapping her hands and following the rhythm.
Following her parents’ lead, the child was also spotted applauding at the end of the song.
Charlotte, who is believed to be attending her first-ever concert tonight, seemed attentive and engaged during the whole show.
When the royal box was urged to imitate one of late Freddy Mercury’s iconic shouts, Charlotte – often spotted waving a Union Jack – was left in stitches.
George and Charlotte were the only two great-grandchildren of the Queen in attendance.
Some 30 members of the Royal Family, including Prince Charles, Camilla, Duchess of Cornwall and the Wessexes, were in the royal box and were spotted singing many of the songs performed on stage.
The Duke and Duchess of Sussex were not in attendance, as previously announced by their spokesperson.
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Meghan Markle and Prince Harry decided to spend the day with their children, as their daughter Lilibet ‘Lili’ Diana turned one today.
The monarch herself was not among those seated in the royal box, but is believed to have watched the spectacle from her residence in Windsor.
And she still managed to be present during the show, as at the beginning of the concert the BBC aired a heartwarming clip featuring the Queen and Paddington bear.
The skit started with the adorable bear joining the Queen at the Palace for tea.
Paddington, known for his love for marmalade sandwiches, thanked Her Majesty for having him as a guest.
The 96-year-old monarch looked on as the bear eagerly drank the whole tea directly from the teapot set on the table and reassured him she did not mind his peculiar manners.
After he dropped the teapot into the cream cakes and splattered one of the Queen’s aides as a consequence, the monarch was left in stitches.
He then said: “Oh dear, perhaps you would like a marmalade sandwich? I always keep one for emergencies.”
To his surprise, Queen Elizabeth replied, “So do I, I keep mine in here for later” before pulling a sandwich out of her handbag.
Princess Charlotte has delighted royal fans by appearing multiple times over the past few days.
On Thursday, she took part in her first-ever public carriage ride through the Mall, heading to Horse Guards Parade to watch the Trooping the Color parade.
She later appeared with her siblings, parents, the Queen and other royals working on the balcony of Buckingham Palace to watch the RAF flypast.
Princess Charlotte was not at yesterday’s service of thanksgiving, attended only by adult royals.
However, she completed her first official visit to Wales earlier today, when she headed to Cardiff Castle with George, Kate and William to meet royal fans and organizers of the local Jubilee concert.