For a royal visit to the Henry Fawcett Children’s Centre in London yesterday, the Duchess of Cambridge looked dashing in a purple silk-crepe Gucci top that she accidentally wore backwards, and we almost missed it. According to Net-a-Porter’s product description of the top, the pussy-bow blouse “features fabric-covered buttons that run down the back.” Similarly, Nordstrom’s description of the shirt says there’s a “row of dainty covered buttons inching down the back.” However, photographs of Kate Middleton show that when she wore the piece, the button closures were at the front instead. That also…