LOL!Prince William Reveals He Wants to Run a Marathon — and Kate Middleton’s Response Is Priceless!

Kate Middleton and Prince William‘s marriage is seriously #RelationshipGoals!

The Duke and Duchess of Cambridge stepped out in London on Tuesday, Jan. 17 at an event promoting their mental health campaign, Heads Together. While speaking to a reporter, William, 34, confessed he hopes to one day run a marathon — and his wife Kate’s response to his admission is nothing short of hilarious!

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“I chatted [with] William, and he has promised that he will run a marathon in Kenya sometime,” Good Morning Britain‘s Sean Fletcher said, according to People.

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Kate, William and Harry in London on Jan. 17.

“Then I spoke to Kate and she said, ‘I’ll believe it when I see it!'” Fletcher added. Too funny!

This isn’t the first time Kate has poked fun at her handsome husband in public. Back in April 2014, the mom-of-two joked about William’s thinning hair while watching a shearing demonstration at the Royal Easter Show.

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“The Prince was interested in the alpaca and as I showed it to them, the Princess said he should put [the animal’s freshly shaved fur] on his head,” farmer Lyn Crejan revealed at the time. “She said, ‘You need it more than me,’ and pointed to his head and he laughed.”

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Kate and William in April 2014.

Earlier this year, Kate took another jab at William during an event to promote their Heads Together project. “Sometimes I still feel like I am 16, to be honest sometimes I still act like I am 16,” Prince Harry‘s older brother said while speaking to a group of high school students.

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“I still think you’re 16,” Kate chimed in to which William responded, “Yes, Catherine often tells me that.” Seriously, could they be any more adorable?!

The couple famously married in a lavish royal wedding in April 2011. They are now parents to two kids, son Prince George, 3, and daughter, Princess Charlotte, 1, who were born in July 2013 and May 2015, respectively.

Click through the gallery below to see Kate and William’s cutest photos together!