He was baptized at the Chapel Royal on the grounds of St James's Palace in London, just like his older brother George.More news: Donald Trump blasts NATO alliance ahead of summit, meeting with Vladimir Putin
It is the first time the Duke and Duchess of Cambridge and their three children have been seen together as a family of five.
Which members of the royal family have worn the replica gown?
Following the service, where Prince Louis was flanked by six godparents, the royals made their way to Clarence House where they enjoyed an intimate afternoon tea with guests.
Since then, the christening gown has become a cultural marker in the regal history books as it has been worn by 62 royals in total including Princes Harry and William.More news: Rockets determined to sign Carmelo Anthony
Uncle Harry has also promised to build the little prince a library in memory of his late mother, Princess Diana, according to the Sun U.K.
Princess Charlotte, teach us your waving technique!
The Duke of Sussex reportedly purchased a first edition copy of "Winnie-the-Pooh" by AA Milne for his youngest nephew. And Louis' non-royal godparents will have influence on the little prince.
William and the Prince of Wales were both christened in Buckingham Palace's Music Room.
The vessel has been used by the British monarchy since 1841, when Queen Victoria's daughter Princess Victoria was christened.More news: Turkey's Erdogan unveils new cabinet