A new group of stamps are being released to celebrate Queen Elizabeth's 90th birthday, but it's the pint-sized future king perched on foam blocks who steals the show with his adorable grin.

Prince George, 2, is making his first appearance on a royal stamp in a picture showing four generations of royalty, including his beloved "Gan Gan,'' better known as the Queen.

Holding the hand of his father, Prince William, George, who is third in line to the British throne, beams while joined by his great-grandmother as well as his grandfather, Prince Charles, in a picture featuring all three of the Queen's direct heirs. George stood on the blocks to make him the exact height of the Queen in order to make the photo work, photographer Ranald Mackechnie told The Telegraph.

“He was absolutely charming, as you can see from the picture,'' Mackechnie said. "You only have a short window of opportunity with small children, but Prince George was on good form and everyone seemed to enjoy seeing him enjoy the day."

The pictures were taken in the summer of 2015 in the white drawing room at Buckingham Palace. Six stamps will be issued on Thursday to celebrate the 90th birthday of the Queen, who has been on the throne since 1952.

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“Because the picture was going to be turned into stamps on a sheet, each person’s head had to be in exactly the right place,'' Mackechnie told The Telegraph. A millimeter the wrong way on the final stamp sheet would have made the perforations too close together, so I had to make sure everyone was spaced the right distance apart.”

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