The Prince of Wales has paid tribute to his "Pa" King Charles the day after the Coronation, saying the late Queen Elizabeth II would be "a proud mother".
Addressing the crowds at Windsor Castle for the Coronation concert, William said his grandmother was "up there, fondly keeping an eye on us".
He said this weekend was "so important" because it was all about service.
Highlighting King Charles' achievements over the last 50 years, William said: "Pa, we are all so proud of you."
And the heir to the throne made his own vow to the nation, saying: "I commit to serve you all. King, country and Commonwealth."
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King Charles and Queen Camilla - colour-coordinated in blue, with the Queen in a royal blue jumpsuit - smiled and waved their own flags during the evening.
The Princess of Wales attended with her and William's oldest children, Prince George and Princess Charlotte. Prince Louis, who has just turned five, stayed at home after his busy day at the Coronation on Saturday.
The Duke and Duchess of Edinburgh were seated near the King and Queen, with Prime Minister Rishi Sunak behind them. Prince Andrew, Duke of York, and his ex-wife the Duchess of York, Sarah Ferguson, also attended, as did Zara Tindall and her husband Mike.
The crowd of 20,000 people got their tickets in a public ballot, with many more watching performances from stars including Katy Perry and Take That on BBC One and BBC Radio 2.
Host Hugh Bonneville - the Paddington and Downton Abbey actor - addressed the royal guests as the show began and acknowledged the King's love of the arts, joking he was "the artist formerly known as prince".
The concert featured musical acts including maestro Andrea Bocelli and Sir Bryn Terfel collaborating on You'll Never Walk Alone, and Olly Murs, who sang Dance with Me Tonight, while there were also spoken word pieces amidst the music.
Cold Feet actor James Nesbitt performed work by poet Daljit Nagra, while fashion designer Stella McCartney spoke about conservation.
There were video cameos from a range of stars, including British acting legend Joan Collins, former James Bond actor Pierce Brosnan, artist Tracey Emin and Welsh singer Tom Jones - all of them recounting little-known facts about the monarch.
And Top Gun actor Tom Cruise delivered a video message from his War Bird plane, saying: "Pilot to pilot. Your Majesty, you can be my wingman any time," before saluting and banking off.
The King seemed to enjoy a skit involving Bonneville and Muppet Show stars Kermit and Miss Piggy, in which Miss Piggy said "King Charlesy Warlesy" was expecting them in the royal box.
At the end of the show, Kermit was seen to have made it to the box, waving a flag in front of Prince Edward but there was no sign of Miss Piggy.