Prince Louie of Wales is the youngest child of Prince William and Princess Katherine. He’s the second grandson of King Charles and currently fourth in line to the British throne. The young prince just melted hearts with a simple yet touching gesture dedicated to his beloved grandparents, King Charles III and Queen Camilla.

When the king stepped out in Singham wearing a rather charming accessory, the thrifty king opted to wear an oversized wool coat that has been in his archive for over four decades, complete with neat lapels and slick tailoring. To mark this big milestone, he appeared to pay a subtle nod to his grandchildren, Prince George, Princess Charlotte, and Prince Louie, by wearing his favorite pink silk tie.

The sweet pink tie was decorated with a herd of candy-blue dinosaurs, which almost went unnoticed in light of his immaculate appearance. It’s no secret that the king’s eldest grandchildren are fans of dinosaurs. Prince William previously revealed that his two sons, George and Louie, have a love for dinosaurs. One of the museum’s most popular exhibits is a large animatronic T. rex, which may have inspired King Charles.

While the event was brimming with holiday cheer, it was Prince Louie who stole the spotlight with his adorable handwritten note for the reigning monarch and his wife. “Thank you to Granny and Grandpa because they have played games with me.”

If it wasn’t heartwarming enough, photographers also captured the young royal looking very serious as he hung his message on the tree. Despite his short stature, Prince Louie had to slightly bend his back to tie the card to a branch securely. The adorable moment, along with a kiss from King Charles, has gone viral after stepping out with his grandchildren and the royal family on Christmas Day.

This comes after Prince Harry claimed he never receives hugs. It follows Prince Harry’s accusation of Charles never giving hugs in his memoir, Spare. Charles opted not to mention either the Duke of Sussex, Harry, or his under-fire brother, Prince Andrew, the Duke of York, in his Christmas Day address.

According to Bishop of Hereford Richard Jackson, “I think what struck me particularly was how extraordinarily affectionate they are. They’re clearly a very close family. All the generations in a sense you felt are part of a family occasion as well as a royal location and a national location.”

A particular favorite scene, on numerous occasions from church at Sandringham to a walkabout in Manchester, is of pale pink silk with a light blue dinosaur Rex pattern printed all over it. King Charles delighted royal watchers when he resumed public-facing duties alongside his wife, Queen Camilla, during a visit to University College Hospital McMillan Center, where they spoke to medical specialists and patients.

The outing marked one of many external engagements His Majesty will undertake in the weeks ahead after confirming the positive effect of his cancer treatment. The charming accessory was decorated with a herd of light blue dinosaurs—a print most likely chosen by his grandchildren.

The tie is believed to have been given to him by a member of his family as a coded play on his new title, Charles III Rex, or C. Rex. The king’s capacity for gloomy introspection appears to have lifted in recent months, and his mood is unquestionably more cheerful these days. The new mood has even permitted a shift in his wardrobe.

Finding gifts for the man who really does have everything might be tricky, but since his accession, his family has given the king several new ties. Is the T. rex motif a humorous play on C. Rex? “I couldn’t possibly comment,” says one of his team with a grin, strongly suggesting it might be. Like his mother, who thoroughly enjoyed being queen even during some very dark days, Charles III is simply very happy with being monarch.

This week, royal fans retreated to the sight of the Prince and Princess of Wales walking hand-in-hand with their children, Prince George, Princess Charlotte, and Prince Louie, from Sandringham House on their way to St. Mary Magdalene Church.

Barbara Lock, from Sleaford, Lincolnshire, has been traveling to Sandringham each Christmas Day for more than 30 years to see the royal family. She says, “She’s a nice girl, she fits in, and I think she’s genuine. She’s lovely, and I like seeing her with the royal family again. I am a royalist. I love the Royals. I shook the king’s hand—that’s made my day. I am happy.”