Prince William and Kate Middleton
Britain's Prince William and Kate Middleton are pictured on a five-day visit to Pakistan. AFP/Aamir QURESHI

Kate Middleton and Prince William are expected to make a big announcement soon and that could amount to a very big and "special surprise." As to what that “surprise” might be, royal watchers only have some speculations to go off of at the moment.

Senior International Correspondent Keir Simmons said on "Today" on Monday that those interested can expect to hear from the British royal couple during the holiday season. While the details of the announcement are being kept under wraps, many are speculating the news could be a baby announcement for the Duke and Duchess of Cambridge.

While the royals only welcomed their newest addition, son Louis, last year, it was reported by The Daily Mail this past spring that Kate wanted to have a fourth child to join son Prince George, 6, and daughter Princess Charlotte, 4.

On Monday, Simmons joked about Kate’s purported baby fever by saying “the 'Today' show family and the royal family are kind of in a competition over who can have the most babies,” referring to "Today" anchor Dylan Dreyer who is due to welcome her second child next month.

Simmons also hinted that the announcement could involve a royal tour, which is likely, given that the couple was seen outside of the country in Pakistan on a mini political tour with government leaders in October.

Another possibility is that the philanthropic couple could be launching another charity or fundraising event. After all, Kate has dedicated a lot of her time to this endeavor, especially with her new duty as Royal Patron of Family Action.

Whatever the "special" royal surprise maybe, fans will find out shortly as the announcement is expected to happen during the holidays.