The Prince of Wales wrote that he and the couple’s three kids — Prince George, Princess Charlotte and Prince Louis — “are so proud” of Middleton.

Prince William praised the 'strength' of his wife, Kate Middleton, in a romantic birthday message posted to Instagram. She turns 43 on Jan. 9.

On Jan. 9, Kate Middleton celebrated her 43rd birthday. Her husband, Prince William, publicly acknowledged the special day on Instagram. Alongside a new black and white photo of the princess wearing a white blouse, a black overcoat, jeans, and a checkered scarf, William wrote, “To the most incredible wife and mother.”