Jul 21, 2015; Sandringham, UK; Prince George birthday. Terms of release, which must be included and passed-on to anyone to whom this image is supplied: USE AFTER 22/10/2015 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 Martio Testino /Art Partner..Prince George, who celebrates his second birthday on Tuesday, with his father, the Duke of Cambridge. The photograph was taken in the gardens at Sandringham House and was part of the series of official photographs taken by Mario Testino following Princess Charlotte's baptism on Sunday 5th July. Picture date: Sunday July 5, 2015. See PA story ROYAL George. Photo credit should read: Mario Testino/PA Wire URN:23620761. (Credit Image: © PA Wire/PA Photos/KEYSTONE Press)
The little prince celebrates his second birthday today, and he's all smiles in this official photo (taken July 5, following his baby sister's baptism), released yesterday by Kensington Palace.
Click ahead to see how he's changed, as we look back over the last two years.
Prince George peeks into Princess Charlotte's pram, pushed by the Duchess of Cambridge, as they leave her baptism in Sandringham, Norfolk.
Photo, Chris Jackson. (PA Wire/PA Photos/KEYSTONE Press)Wearing the same outfit his father did at the 1984 birthday ceremony, Prince George's adorable antics light up the crowd at Buckingham Palace for his grandmother's birthday June 13th.
(Photo, Patrick van Katwijk/ZUMAPRESS.com/Keystone Press.)The prince cuddles up to his new baby sister, Princess Charlotte, at Anmer Hall in Norfolk.
(Photo, Duchess of Cambridge/PA Wire/PA Photos/KEYSTONE Press.)The little royal shows off his sunny disposition as he sits atop the stairs of Kensington Palace's courtyard in one of three official Christmas photos released late last year.
(Photo, TRH The Duke and Duchess of Cambridge/National Pictures/KEYSTONE Press.)Catherine and Prince George watch Dad and uncle Harry play in the Jerudong Trophy charity polo match at Cirencester Park Polo Club on June 15, 2014.
Photo, Max Mumby/Indigo/Getty Images.As part of their three-week trip to Australia and New Zealand, Kate and George depart Australia from Defence Establishment Fairbairn on April 25, 2014 in Canberra.
Photo, Samir Hussein/WireImage.Prince George of Cambridge and Catherine, Duchess of Cambridge arrive in New Zealand at Wellington Airport on April 7, 2014. The Duke and Duchess of Cambridge are on a three-week tour of Australia and New Zealand, the first official trip overseas with their son, Prince George of Cambridge.
Photo, Danny Martindale/WireImage.The Royal couple will visit more than a dozen cities throughout New Zealand and Australia including Christchurch and Auckland.
Photo, Danny Martindale/WireImage.Kate Middleton carries son Prince George of Cambridge at his christening by the Archbishop of Canterbury in London, England.
Photo by John Stillwell - WPA Pool /Getty Images.Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge (wearing Alexander McQueen), arrive with their son Prince George of Cambridge at Chapel Royal in St James's Palace in central London, ahead of the christening of the three month-old prince.
Photo John Stillwell/AFP/Getty Images.In this image provided by Kensington Palace, Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge pose for a photograph with their son, Prince George Alexander Louis of Cambridge, surrounded by Lupo, the couple's cocker spaniel, and Tilly the retriever (a Middleton family pet) in the garden of the Middleton family home in August 2013 in Bucklebury, Berkshire.
Photo, Michael Middleton/WPA Pool/Getty Images.The proud parents look comfortable and happy with their new life at home with baby George.
Photo, Michael Middleton/WPA Pool/Getty Images.The Duke and Duchess leave the Lindo Wing with their newborn son.
Photo, Dave J Hogan/Getty Images.The glowing mom steps out with her new son.
Photo, Scott Heavey/Getty Images.A close up shot of the new, as of yet named, Prince of Cambridge.
Photo, Peter Macdiarmid/Getty Images.Carole Middleton and Michael Middleton arrive at the Lindo Wing to visit the Duchess Of Cambridge and her newborn son at St Mary's Hospital on July 23.
Photo, Dave J Hogan/Getty Images.Prince Charles, Prince of Wales and Camilla, Duchess of Cornwall arrive at The Lindo Wing before visiting Catherine, Duchess Of Cambridge and her newborn son at St Mary's Hospital.
Photo, Dave J Hogan/Getty Images.Prince William and Kate Middleton leave St. Mary's hospital with their safely-secured new son. The baby is third in line to the throne and becomes the Prince of Cambridge.
Photo, Oli Scarff/Getty Images.The Duchess of Cambridge with her new son, weighing 8 pounds, 6 ounces, with Prince William at her side.
Photo, Peter Macdiarmid/Getty Images.Kate Middleton carefully passes her hubby, Prince William, their new son to hold in front of St. Mary's hospital in London.
Photo, Chris Jackson/Getty Images.Kate Middleton and Prince William stand outside St. Mary's hospital looking fresh-faced...we don't know how they do it!
Photo Oli Scarff/Getty Images.Taking domestic life into their own hands, Prince William and Kate Middleton leave St. Mary's hospital with their newborn son safely sitting in the back seat of their black SUV.
Photo, Chris Jackson/Getty Images.Related:
Our royal baby, ourselves: Why we're obsessed with Princess Charlotte
Prince Harry's life lessons for the new royal princess
In photos: A look back at Kate Middleton's style
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