Princes George and Louis and Princess Charlotte, three of Queen Elizabeth II’s great-grandchildren, baked cupcakes to celebrate the queen’s Platinum Jubilee.

The siblings are seen in a video shared on Twitter baking cupcakes alongside their mom Kate, Duchess of Cambridge.

According to the video’s caption, the cupcakes are for a Platinum Jubilee street party taking place Sunday in Cardiff.

Kate and her husband, Prince William, brought George and Charlotte with them on a royal engagement Saturday in Cardiff. The family visited Cardiff Castle and met performers and crew taking part in a jubilee concert at the castle.

As music’s biggest stars rocked Buckingham Palace Saturday night at the Platinum Party at the Palace concert for the queen, her son and grandson took the stage to honor Her Majesty too.

Prince Charles, Elizabeth’s oldest child and heir to the throne, thanked her for her 70 years of service to the U.K., and for being his mom.

“The scale of this evening’s celebration -- and the outpouring of warmth and affection over this whole Jubilee weekend -- is our way of saying thank you, from your family, the country, the Commonwealth, in fact the whole world,” Charles said, with his wife Camilla, Duchess of Cornwall, by his side. “On behalf of us all, I wanted to pay my own tribute to your lifetime of selfless service.”

“Your family now spans four generations,” said Charles, who was 4 years old when his mom became queen. “You are our Head of State. And you are also our mother.”

As Charles delivered his remarks, images of the queen that he selected himself were projected onto Buckingham Palace. He encouraged the crowd of thousands to cheer loudly enough that Elizabeth could hear them at Windsor Castle.

Charles paid tribute to both Elizabeth, who, at age 96, did not attend the concert, and his father, Prince Philip, who at the time of his death last year at age 99 had been married to Elizabeth for 73 years.

“My Papa would have enjoyed the show and joined us wholeheartedly in celebrating all you continue to do for your country and your people,” said Charles.

Prince William, second in line to the throne, focused on the conservation efforts of the royal family, led by Elizabeth.

“It’s my firm hope that my grandmother’s words are as true in 70 years’ time as they are tonight that as nations we come together in common cause, because then there is always room for hope,” he said.

Queen Elizabeth II is not attending Saturday’s star-studded concert at Buckingham Palace, but quickly stole the show.

The 96-year-old queen starred alongside Paddington Bear in a video that kicked off the Platinum Party at the Palace.

In the video, Paddington takes a marmalade sandwich out of his hat to offer to Elizabeth, only for her to show the bear that she keeps a hidden stash too, in her handbag.

Later in the video, Paddington thanks the queen for her 70 years of service, saying, “Happy Jubilee Ma’am. And thank you. For everything.”

Elizabeth then replies, “That’s very kind.”

A palace spokesperson told ABC News of the sketch, "Her Majesty is well known for her sense of humor, so it should be no surprise that she decided to take part in tonight’s sketch. There was an interest in the filming and animation process and the opportunity to invite a famous bear to tea was just too much fun to miss.”

Britain’s royal family got to sit back and listen to some of music’s biggest stars Saturday night at a Buckingham Palace concert for Queen Elizabeth II’s Platinum Jubilee.

Prince William and his wife Kate, Duchess of Cambridge, and their two oldest kids, Prince George and Princess Charlotte, are among the royals attending the Platinum Party at the Palace, watching stars including Elton John, Alicia Keys and Diana Ross perform.

Also present from the royal family are three of Queen Elizabeth II's four children, Princes Charles and Edward and Princess Anne, and their spouses.

Nearly all of the queen's grandchildren are these as well, including Princesses Beatrice and Eugenie, Peter Phillips, Zara Tindall, Lady Louise Windsor and James, Viscount Severn.

The queen, the first British monarch to reach 70 years on the throne, is not attending the concert but will be honored in several speeches and tributes.

Also absent from the royal family booth are Prince Harry and Meghan, Duchess of Sussex. The California-based Sussexes traveled to the U.K. for the queen’s Platinum Jubilee but spent Saturday, their daughter Lili’s first birthday, “together privately as a family,” according to a spokesperson.

Queen Elizabeth II shared a written thank you message on Sunday to mark the end of four days of celebrations for her Platinum Jubilee.

"When it comes to how to mark seventy years as your Queen, there is no guidebook to follow. It really is a first. But I have been humbled and deeply touched that so many people have taken to the streets to celebrate my Platinum Jubilee," Elizabeth wrote. "While I may not have attended every event in person, my heart has been with you all; and I remain committed to serving you to the best of my ability, supported by my family."

"I have been inspired by the kindness, joy and kinship that has been so evident in recent days, and I hope this renewed sense of togetherness will be felt for many years to come," the queen continued. "I thank you most sincerely for your good wishes and for the part you have all played in these happy celebrations."

The queen signed her message with her first name, Elizabeth, followed by the letter R, which stands for Regina, the Latin word for queen.