Catherine, Princess of Wales, turns 43 on Jan. 9 and received a sweet message from her husband, Prince William.

The Prince of Wales posted a birthday message for his wife, Catherine, Princess of Wales to social media on Thursday to celebrate her 43rd birthday.

The Princess of Wales said her cancer diagnosis came as a "huge shock." Kate Middleton and Prince William share three kids: George, Charlotte and Louis.

Catherine, Princess of Wales, revealed last March that she had been diagnosed with an unspecified cancer and was undergoing chemotherapy.

After a year that saw her tested to her limits, Kate is a ‘different person’ – determined to do things her way

Prince William praised the strength of the Princess of Wales after a turbulent year, offering a 43rd birthday wish on social media that described her as an incredible wife and mother

The Prince of Wales said she is "the most incredible wife and mother" and included a message from their children.

Prince William is celebrating his love and admiration for Kate Middleton as she marks her 43rd birthday. In a message posted to the couple's social media, William, 42, paid tribute to Kate after a year in which she had a major operation,

Prince William is celebrating Kate Middleton on her 43rd birthday. In a break with palace tradition, the Prince of Wales wrote a personal, heartfelt message in honor of his wife's special day alongside a new photo of the princess on Instagram.