Kate could also be seen wearing her sapphire and diamond engagement ring, which used to belong to William's late mother, Princess Diana. Now royal historian Dr Tessa Dunlop claimed the new picture carried a hidden meaning in how the younger generation of royals want to portray themselves to the public.

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 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.

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.