Even though King Charles is continuing treatment for an unspecified type of cancer, the monarch is not above cracking some tried-and-true grandpa jokes.

While hosting a state banquet in honor of Japan’s Emperor Naruhito and Empress Masako, King Charles gave a speech highlighting how Japanese culture and U.K. culture have influenced each other, especially when it comes to the decades-old phenomenon Pokémon.

“I am only sorry to report that I haven’t had any better luck with more recent attempts at fishing—the Pokémon phrase ‘gotta catch ‘em all’ may resonate with my grandchildren, but for me, it is, perhaps, aspirational!” King Charles joked, while referring to his less-than-stellar fly fishing skills.

Apparently, Prince George, Princess Charlotte, and Prince Louis—and perhaps Prince Harry’s children, Prince Archie and Princess Lilibet—are big fans of the Japanese media franchise that spans video games, animated television series and blockbuster movies, and an extremely popular trading card game.

In a video captured by Sky News and shared on X, formerly known as Twitter, King Charles’ son Prince William was seen reacting to his dad’s, well, dad joke, flashing a smile while his father carried on with remarks and the night’s proceedings.

According to a source who recently spoke to Us Weekly, King Charles is heartbroken that he has not had the opportunity to spend more time with Prince Harry’s children, and “longs for the same relationship with his American grandkids” that he enjoys with his grandchildren living in the United Kingdom.

“It’s left a massive hole in his heart that he’s only spent a few fleeting days with them and then video calls on important days,” the source told the publication at the time, referring to the monarch’s relationship with Prince Archie and Princess Lilibet.

“King Charles would love to be closer to Harry and to have a relationship with his son that actually works,” royal author Tom Quinn told The Mirror in a recent interview. “But this depends on Harry giving his father cast-iron guarantees that there will be no more books and no more embarrassing interviews.”

Quinn went on to say that the monarch has "had discussions about an official visit to the United States at some time in the future."

"There is no doubt if it goes ahead he would build in time to visit his youngest son and his grandchildren,” Quinn added. “But there are mountains of planning to be overcome before that becomes even a remote possibility.”

According to a recent report from The Mirror, King Charles is not content with a few scarce video calls with his grandchildren living across the pond.

"The King is absolutely committed to being present in all of his grandchildren’s lives,” a source told the publication at the time. “He values family above everything, and whatever the course of his relationship with his son, he would never be content with just seeing his grandchildren on the odd video call.”

The same source added that Queen Camilla is "also understood to be a driving force behind his decision to ramp up efforts to see his other grandchildren.”