The Archbishop of Canterbury, Justin Welby, will conduct the christening.at the Chapel Royal, St James's Palace, London.
Prince Louis will be baptised at the same place as his older brother George. The original garment was created for Queen Victoria for the christening of her eldest daughter, Princess Royal Victoria, but is now considered too fragile for use. Certain parts of their eight-layer confection were reserved for the christenings of their children, an age-old royal tradition.
The Queen is head of the Church of England and Louis' father William will one day take on this role when he becomes king.
It is unknown whether William will get some quality time to celebrate his birthday with his wife and three children, although past year they enjoyed celebrating William's day in private. It will be a small gathering similar to George's christening, to which only 22 guests were invited.
Charlotte's baptism in 2015 involved the Cambridge family walking to church past well-wishers. William and Catherine have picked mainly friends rather than royal relatives as godparents to their older two children, George, 4, and Charlotte, 3.
The Queen, Prince Charles and the Duchess of Cornwall are set to attend.
"The Duke and Duchess would like to thank members of the public for their kind messages following the birth of Prince Louis, and for Princess Charlotte's third birthday".
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