Prince George Makes His Postage Stamp Debut for Queen's 90th Birthday

The royals' photo was taken in Buckingham Palace last year.

Ranald Mackechnie was chosen to shoot the special photo of the four generations. The royals initially planned to shoot the iconic photo in Buckingham Palace's Yellow Drawing Room but later decided that the White Drawing Room would capture the moment more effectively.

The queen will make a special visit to the Royal Mail near her home at Windsor Castle today with Prince Philip to mark the 500th anniversary of the Royal Mail.

The special stamps go on sale Thursday.