The fifth in line to the throne was christened in Chapel Royal at St James's Palace on July 9, with numerous royals from his father's side and non-royals from his mother's side present.
The four images were taken by celebrity photographer Matt Holyoak following the baptism in The Chapel Royal at St James's Palace.
The third image shows the Cambridges as a family of five, with Kate Middleton lovingly looking down at her son as little Charlotte and George stand nearby with William. Louis wore the Royal Family's replica heirloom christening gown made from Honiton lace.
All babies are cute, the saying goes, but royal babies are especially adorable, even in the context of official, for-the-history-books photographs.
A statement released by the royal family also revealed Louis' Godparents were Nicholas van Cutsem, Guy Pelly, Harry Aubrey-Fletcher, Laura Meade, Robert Carter and Lucy Middleton.
But the formal moment was broken by Charlotte, 3, who is clearly very affectionate with her baby brother.
The youngest prince was born on April 23 and was baptized on July 9.
See more of Prince Louis' christening in the video below.
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