In another photograph taken in the garden of the Queen's Norfolk home, he is grabbing his father's hair with a more familiar pout on his face.
The photographs were taken immediately after the christening service at the church of St Mary Magdalene, Sandringham.
A Kensington Palace spokesman said: "The Duke and Duchess of Cambridge and their whole family had a wonderful day on Sunday and were delighted to share the special occasion with the thousands of people who came to Sandringham.
"They are very happy to share these photographs and hope that everyone enjoys them as much as they do."
Testino said: "Photographing Princess Charlotte's christening was an amazing experience. What impressed me the most was the energy of the family, and of that between the Duke and Duchess. One sees how solid they are together and one gets a sense of their strong family values.
"It was incredible to be able to document four generations of the British royal family together - the monarch and three heirs to the throne - and very heartwarming to see the close relationship between them all.
"I am overwhelmed and honoured to be chosen to document this occasion and to carry on the documentation of the family that is the soul of this country, a country that has given me so much."
The Peruvian was chosen by the Duke and Duchess after they enjoyed working with him for the official photographs taken to celebrate their engagement. He has a long association with the royal family, in particular Diana, Princess of Wales, for whom he was a favourite.
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