Kate Middleton must know the number one style rule of the royals: If it ain't broke, don't fix it. (Case in point: Queen Liz always wearing bright colors, Meghan Markle working it in Givenchy, Camilla Parker Bowles rocking pearl chokers...)
So when the Duchess of Cambridge broke her own style "rule" of summer on Tuesday at day one of the Royal Ascot horse races, we were quite surprised.