Princes William, Harry React to Royal Baby News

Prince Harry calls the news that he will be an uncle again, "very exciting."

“Great,” Prince Harry, 29, said when asked by BBC News’ Peter Hunt today at an event in London for the Invictus Games, an athletic competition for wounded warriors.

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“I can’t wait to see my brother suffer more and, with any luck, if it’s a girl he’ll suffer even greater,” Harry joked of William becoming a father-of-two. “I’d love to see him try and cope with that.”

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The duchess is not yet 12 weeks pregnant, Palace officials told ABC News. She was scheduled to travel to Oxford, England, today with William for an event but is instead being treated by doctors at Kensington Palace.

“She's feeling OK," Prince William said in Oxford. "[It's the] early days but I hope things settle down and she feels a bit better."

Prince Harry too said that his sister-in-law was feeling “pretty poorly” the last time he saw her, although he did not say when that was.

“Luckily I’m not a woman, so I don’t have to go through that and nor do you,” Harry said to Hunt. “So it’s a pretty horrible thing to have to go through but she’s doing…as best she can.”

“I hope my sister-in-law gets better soon and the two of them have the opportunity to, I suppose, go through the whole process again in a little bit of peace and quiet,” Harry added.

News of Middleton’s first pregnancy, with Prince George, broke in December 2012 when she was admitted to King Edward VII Hospital in London with the same illness.

She gave birth to George the following July and he is now a happy toddler, who is walking and learning to swim.

When Prince George was first born, it was Harry who joked of how involved he would be with his first nephew, at the time telling reporters, "I only hope my brother knows how expensive my babysitting charges are.”

Harry did not say whether Prince William will have to write even bigger checks with this second baby, but did say his nephew will be "thrilled" by having a playmate.

“I think George will be over the moon,” Harry said of his 14-month-old nephew. “He’ll be thrilled having another younger smaller brother or sister. So we’ll wait and see."

“The family continues to grow,” he said.