Terms of release, which must be included and passed-on to anyone to whom this image is supplied: For use in perpetuity in UK and Realm Nations. USE AFTER 10/10/2015 elsewhere must be cleared by Art Partner. This photograph is for editorial use only. NO commercial use. NO use in calendars, books or supplements. Use on a cover, or for any other purpose, will require approval from Art Partner and the Kensington Palace Press Office. There is no charge for the supply, release or publication of this official photograph. This photograph must not be digitally enhanced, manipulated or modified and must be used substantially uncropped. Picture must be credited: copyright Mario Testino /Art Partner. File photo dated 05/07/15 of the Duke and Duchess of Cambridge with their children, Prince George, and Princess Charlotte, in the Drawing Room of Sandringham House with Queen Elizabeth II (seated right) and (standing, from left), Michael Middleton, Pippa Middleton, James Middleton, Carole Middleton, the Prince of Wales and the Duchess of Cornwall and the Duke of Edinburgh. Prince George will celebrate his second birthday tomorrow.