LONDON, ENGLAND - NOVEMBER 7:  Catherine, Duchess of Cambridge speaks to Peter Fonagy at the 2017 Gala Dinner for The Anna Freud National Centre for Children and Families (AFNCCF) at Kensington Palace on November 7, 2017 in London, England. (Photo by Frank Augstein - WPA Pool/Getty Images)
LONDON, ENGLAND - NOVEMBER 7:  Catherine, Duchess of Cambridge arrives at the 2017 Gala Dinner for The Anna Freud National Centre for Children and Families (AFNCCF) at Kensington Palace on November 7, 2017 in London, England. (Photo by Frank Augstein - WPA Pool/Getty Images)
LONDON, ENGLAND - NOVEMBER 7:  Catherine, Duchess of Cambridge speaks to various guests at the 2017 Gala Dinner for The Anna Freud National Centre for Children and Families (AFNCCF) at Kensington Palace on November 7, 2017 in London, England. (Photo by Frank Augstein - WPA Pool/Getty Images)
LONDON, ENGLAND - NOVEMBER 7:  Catherine, Duchess of Cambridge speaks to Peter Fonagy at the 2017 Gala Dinner for The Anna Freud National Centre for Children and Families (AFNCCF) at Kensington Palace on November 7, 2017 in London, England. (Photo by Frank Augstein - WPA Pool/Getty Images)
LONDON, ENGLAND - NOVEMBER 7:  Catherine, Duchess of Cambridge speaks to Peter Fonagy at the 2017 Gala Dinner for The Anna Freud National Centre for Children and Families (AFNCCF) at Kensington Palace on November 7, 2017 in London, England. (Photo by Frank Augstein - WPA Pool/Getty Images)