TRH Duke & Duchess of Sussex
Clarence House
London SW1A 1BA
UNITED KINGDOM
They should reply with their usual postcard sized photo with typed message on the back. It should be something similar to the reply for the Cambridge's pregnancy.
Expect longer response times, as they will be getting a lot more mail and are still behind on replies for Prince Louis's birth & Sussex wedding. So, while some of you may get a reply quickly, some of us may be waiting for many months.
