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Prince William and Duchess Catherine are joined by their son, and heir to the throne, Prince George, and their daughter Princess Charlotte.

In the message, they wish readers a merry Christmas and say they are "looking forward to their first Christmas as a family of four."

The photo was taken in October outside their London home.

In addition to the photo, NBC News reports that the future king will be attending nursery school at the end of January. The 2-year-old will attend a Montessori nursery school near the family's country home in Norfolk.