Photographer Matt Holyoak spoke of photographing the family for the special occasion, saying: "I was truly honoured at being asked to take the official photographs at the christening of Prince Louis, and to witness at first hand such a happy event".
And with the Queen and Prince Philip absent, it is Kate's family who dominate in this image, one of four taken by photographer Matt Holyoak and released today by Kensington Palace.
The Royal Family looked prim and proper as they gathered for official photos, taken after the service on Monday afternoon by Matt Holyoak. The Duchess is pictured wearing an Alexander McQueen dress and headpiece designed by Jane Taylor.
Louis was christened in the Chapel Royal at St James's Palace last Monday, before the families then reassembled at nearby Clarence House.
Her husband, multi-millionaire hedge fund manager James, whom she married past year, makes the family group, along with her bearded brother, also called James.
The ex-actress can be seen standing in between Harry and Camilla while beaming widely.
On the sofa, William has a protective arm around George - who will be five next Sunday - while cheeky Charlotte stares challengingly at the camera as if plotting her next piece of mischief.
In another, the royals are joined by Catherine's parents, Carole and Michael Middleton, sister Pippa Matthews and her husband James, and brother James Middleton.
But without doubt, Prince George, who will turn five this month, stole the scene with his massive grin as he sat on his father's lap.
Mr Holyoak said: 'Everyone was so relaxed and in such good spirits, it was an absolute pleasure.
Prince Louis Arthur Charles was born on 23 April 2018 in the Lindo Wing of St Mary's Hospital in London as the third child of the Duke and Duchess of Cambridge.
'I only hope I have captured some of that joy in my photographs'.