William & Kate Baby Bliss

The royal family is growing again! Prince William and Duchess Kate are expecting their fourth child later this year, a palace source tells OK!

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Duchess Kate was glowing. On May 20, she and husband Prince William took Queen Elizabeth II on a tour of a gorgeous garden she’d helped design for the Chelsea Flower Show. “Kate was very happy but also acting oddly. She kept her hands in front of her stomach, almost as if she was trying to hide something,” a witness tells OK!, adding that the normally pin-thin 37-year-old also appeared to have a small bump. “By the end of the tour, everyone was buzzing that she might have another baby on the way!”

It seems they were onto something. “William and Kate are expecting their fourth child,” a palace source tells OK!, adding that they’re both over the moon. “Kate’s due in December, which will make the holidays even more exciting!” And while the future king and queen — who are already parents to Prince George, 5, Princess Charlotte, 4, and Prince Louis, 13 months — had talked about someday expanding their family, they didn’t expect it to happen so soon. Adds the source: “This pregnancy was a very happy surprise.”

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