Prince Harry has yet to babysit his niece and nephew.
Harry's brother Prince William is father to two-year-old Prince George and seven-month-old Princess Charlotte.
But while William is being kept busy with his fatherly duties, Harry has yet to experience what being an uncle really involves.
The revelation was made during a chat with Declan Donnelly and Ant McPartlin for new programme 'When Ant and Dec Met the Prince of Wales: 40 Years of the Prince's Trust'.
Declan told Hello magazine: "We talked more about William being a father and whether Harry had babysat. He hadn't, but he will. He promised."
The presenting duo also revealed that Harry often goes for dinner with William and his wife Kate, the Duchess of Cambridge.
Dec continued: "Like Ant and me, William and Harry live very close to each other. They live in different parts of Kensington Palace. We were asking William whether Harry comes round for his dinner He does, but if William goes round to Harry's place there's never anything in the fridge, so Kate always invites him round.
"I told Harry that once he gets sick of Kate and William's cooking, that's when he got to find himself a wife. We were all joking with him. He was taking flak from all sides and nodding his head like he's heard it a hundred times before his brother."