The eight-year-old was brought up in conversation by the Prince of Wales
Princess Charlotte's "favourite joke" was shared by Prince William in a cringeworthy video today.
The Prince of Wales visited the Midlands today where he spoke with school students about mental health initiatives.
During a visit to St Michael's Church of England High School in Rowley Regis, William, 41, learnt about the award-winning student-led initiatives available to pupils to support their mental health and wellbeing.
Prince William said: "I am with the gang here talking about male mental health and I've been asked to produce a dad joke."
He also made a slight dig at a popular British comedian during the conversation.
William added: "I'm trying to channel Jack Whitehall, because most of his jokes are pretty dad-like.
"What I'll do is I'm going to say a joke that's Charlotte's favourite joke at the moment, she keeps telling me, I'll do that instead.
"You're going to have to interact with me, it's not a joke I can tell straight away."
Before the boys had a chance to reply "Interrupting cow who?", William loudly went "Moo!"
The boys groaned in response to the cringeworthy joke, before William said: "Yep, that's what I get a lot at home at the moment.
"That's the greatest one I can think of, it's clean and broadcastable."
Prince William visited St Michael's School today after a student named Freddie Hadley wrote him a letter last year, inviting him to learn about their mental health initiatives.
The duo were photographed outside the school as William told the young boy: "I'm here now."
