Prince George and Princess Charlotte Dance Along to Lionel Richie at Coronation Concert

Kate Middleton and Prince William's children watched acts like Katy Perry at Windsor Castle, waving Union Jack flags throughout the show

Prince George and Princess Charlotte are ready to party!

Kate Middleton and Prince William's two eldest children joined the royal family at Sunday's Coronation Concert, continuing the celebrations after King Charles and Queen Camilla's crowning ceremony took place on Saturday. They took their spots in the front row of the royal box.

After participating in the coronation festivities yesterday, 5-year-old Prince Louis did not attend the Coronation Concert.

While Prince George wore his signature suit and tie in a matching moment with dad, Princess Charlotte wore a Self-Portrait tiered chiffon dress — the same brand worn by Kate at Friday evening's Buckingham Palace reception for overseas guests to the coronation. She later covered up in a white coat by Amaia.

Prince George, 9, and Princess Charlotte, 8, were spotted clapping along to acts and waving Union Jack flags. They lit up when Miss Piggy and Kermit made a surprise appearance saying they were looking for their seats in the royal box. Towards the end of the show, Kermit seemed to find his way to the box — waving a flag right in front of Prince Edward and Sophie, the Duke and Duchess of Edinburgh!

The Wales kids joined the rest of the crowd in standing up and dancing along — and waving their flags — to Lionel Richie perform "All Night Long." The singer also sang "Easy (Like Sunday Morning)."

Related:The Best Moments You May Have Missed from King Charles and Queen Camilla's Coronation

Princess Charlotte was spotted singing along to Katy Perry's performance of "Roar" as drones in the sky formed a lion — a key part of King Charles and Queen Camilla's coats of arms. The pop star wore a custom Vivienne Westwood gown for the show.

Perry, who attended the crowning at Westminster Abbey on Saturday, excitedly told the crowd that she brought her mom to the U.K. and that she was staying in Windsor Castle before performing "Firework," dedicated to King Charles and his charity work.

Lionel Richie and Katy Perry — two American Idol judges who both have close connections to King Charles — headlined the show, which featured an eclectic lineup of performers such as Andrea Bocelli, Sir Bryn Terfel, Freya Ridings and Alexis Ffrench.

Related:How Prince George Made History at His Grandfather King Charles' Coronation

The concert, broadcast live from the grounds of Windsor Castle and hosted by Paddington star Hugh Bonneville, was meant to "celebrate the Coronation of Their Majesties The King and The Queen in front of 20,000 members of the public and invited guests," not to mention the many viewers watching the BBC broadcast from home.

Nicole Scherzinger performed "Reflection" from Mulan as pianist Lang Lang played, and Olly Murs was one of the first performers to take the stage at the show.

Related:Andrea Bocelli Reveals King Charles and Queen Camilla's Song Request for Coronation Concert (Exclusive)

Opera star Andrea Bocelli performed "You'll Never Walk Alone" as a duet with Bryn Terfel — which Bocelli told PEOPLE was a special request from King Charles and Queen Camilla.

"The King and the Queen Consort have demonstrated their appreciation of art and good music — which are gifts from the heavens, and that, as they lift the spirit, contribute to spreading good. This is per se already a reason for all of us to be excited," Bocelli, 64, told PEOPLE ahead of the concert. "As for my performance, they have indeed specifically requested a song that is very dear to me as well: 'You'll Never Walk Alone,' a touching, intense and evocative score, a true tribute to solidarity."

Tom Cruise, Dame Joan Collins, Bear Grylls and more also made appearances in pre-recorded sketches, including some segments featuring the famous faces sharing little-known facts about King Charles.

British pop group Take That closed out the show.

Princess Charlotte and Prince George — along with mom Kate — looked on proudly as dad Prince William took the stage with a speech to his father, King Charles.

The heir to the throne began, "I want to say a few words about my father and why I believe this weekend is so important. But don't worry, unlike Lionel, I won't go on all night long."

Referring to Queen Elizabeth, "As my grandmother said when she was crowned, 'Coronations are a declaration of our hopes for the future,' " Prince William said, quoting her coronation speech from 1953. "And I know she's up there, fondly keeping an eye on us. She would be a proud mother."

In addition to a star-studded concert, the night doubled as a light show with drones and wristbands worn by attendees that lit up.

Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!

Earlier in the day, Prince William and Kate attended a Big Lunch event at Windsor Castle — and the Prince of Wales shared that his daughter was resting up from the coronation.

"She's very tired after yesterday," he told a girl, according to Hello! magazine. "She's having a quiet day at home. It was making sure her little brother behaved himself," he added, referring to Princess Charlotte minding Prince Louis during the historic ceremony.

In addition to being a big day for King Charles and Queen Camilla, the coronation marked a special occasion for Prince George. The young royal, who is second in line to the throne after dad Prince William, served as a Page of Honor for his grandfather at the crowning ceremony. His participation in the coronation marked the first time in modern royal history that a future monarch was officially involved in such a service. According to The Telegraph, George became the youngest future king to play an official role at a coronation.

RELATED VIDEO: Lionel Richie Teases Set List for King Charles' Coronation Coronation Concert: 'It's a Royal Secret'

King Charles was 4 at the coronation of his mother Queen Elizabeth in 1953, but he was only brought in to watch the investiture segment (highlighted by the moment of crowning) during the three-hour service. Queen Elizabeth was 11 at the coronation of her father, King George VI, in 1937 and similarly witnessed the festivities from the Royal Gallery, per Westminster Abbey.

For more People news, make sure to sign up for our newsletter!

Read the original article on People.