LONDON, ENGLAND - MAY 04:  Catherine, Duchess of Cambridge with Alexandra Shulman (R) and Nicholas Cullinan (L) visit the "Vogue 100: A Century Of Style" exhibition at National Portrait Gallery on May 4, 2016 in London, England.  The Duchess appears on the cover of the centenary issue in June 2016.  (Photo by Ian Gavan - WPA Pool/Getty Images)