Kate, the Princess of Wales, turns 43 on Thursday, capping what was a tumultuous year for the mother of three and wife of Prince William. Kate, who was born Jan. 9, 1982, is expected to spend her birthday privately with William and their kids -- Princes George and Louis and Princess Charlotte -- at home in Windsor, England.

Kate will use videos to speak directly to the public after discovering powerful impact of her messages during cancer treatment

Princess Kate is celebrating her 43rd birthday. Her husband, Prince William, honored the "most incredible wife and mother" in a new post.

Kate completed her laid back look with her sapphire and diamond engagement ring. This piece of jewelry belonged to her late mother-in-law, Princess Diana. William’s post came as

Prince William has shared a new black and white photo of his wife Princess Kate to social media in honour of her 43rd birthday.

In the photo, Middleton traded sleek coats and heels for something more casual. She wore a dark blazer jacket rolled and cuffed at the sleeves with a crisp white button-up top. Completing the outfit was a checked plaid printed scarf worn around the neck and fitted dark jeans with light whiskering at the hips.

Prince William has broken royal tradition with a "powerful statement" to Princess Kate, according to a royal historian. The future King released the statement alongside a photo of Catherine on the Prince and Princess of Wales's joint social media account.