Prince William Reveals the 'Really Tough Question' That George, Charlotte and Louis Ask Him 'Regularly'

Prince William offered a glimpse into his home life with Prince George , Princess Charlotte and Prince Louis , sharing one of the questions they ask him most often.

The Prince of Wales, 42, made the revelation in conversation with Australian television star Robert Irwin while they were out on a nature walk on Signal Hill, Cape Town on Nov. 5. Prince William is in South Africa for the fourth annual Earthshot Prize Awards ceremony, the prestigious contest he founded in 2020 to promote solutions to the world's most pressing environmental challenges, which Irwin supports as a global ambassador.

"I have to ask — we're in South Africa, one of the most amazing countries and continents for wildlife — do you have a favorite African animal?" Irwin asked Prince William.

"It's a really tough question. My children ask me this regularly," the royal replied, referencing his children George, 11, Charlotte, 9, and Louis, 6, whom he shares with wife Kate Middleton . "I think I'm going to have to say the cheetah."

Irwin said that Prince William's pick was "very cool," and that he likes a color-changing reptile.

"It's chameleons for me. The unsung hero. I love 'em," he said. Irwin, 20, is the son of the late "Crocodile Hunter" Steve Irwin and continues his father's legacy in conservation work alongside his mother Terri and sister Bindi at the Australia Zoo.

The Prince of Wales — who wore his "Papa" friendship bracelet from Princess Charlotte for his second day in South Africa had joined the Crikey! It's the Irwins alum for a walk on Signal Hill to highlight biodiversity.

There, the Earthshot global ambassador asked the royal how he was enjoying South Africa so far, and William said that all was well.

"Good thanks. Having a lovely time here," the royal replied, while congratulating Irwin for being a "fantastic ambassador" for the prize which will hold its glittering awards ceremony on Wednesday, Nov. 6.

"Tomorrow night — it's going to be amazing," Irwin added.

On Wednesday, five of the 15 Earthshot Prize finalists will each receive a $1.3 million to scale their solutions to size and help accelerate positive change for the planet, described by Prince William's team as his "Super Bowl moment."

The royal dad's reference to his children around the animal banter calls back to when Prince George, Princess Charlotte and Prince Louis sweetly spoke on camera for the first time in 2020, as they each asked Sir David Attenborough a question to help raise awareness to the challenges of the natural world.

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Prince George, then 7, was first to speak, and said, "Hello David Attenborough, What animal do you think will become extinct next?"

His cameo was followed by Princess Charlotte, then 5, who said, "Hello David Attenborough, I like spiders. Do you like spiders too?"

Prince Louis, then 2, had a breakout moment when he asked Attenborough "What animal do you do like?" with an adorable way of saying "animal."