The names of Prince George's seven godparents have been announced ahead of his christening later.
They are Oliver Baker, Emilia Jardine-Paterson, Earl Grosvenor, Jamie Lowther-Pinkerton, Julia Samuel, William van Cutsem and Zara Tindall.
Zara Tindall, wife of former England rugby international Mike Tindall, is Prince William's cousin.
The Archbishop of Canterbury will christen the three-month-old prince at St James's Palace in central London.
The private service will take place at 15:00 BST and last about 45 minutes.
Mrs Jardine-Paterson, who uses her maiden name d'Erlanger in her working life as an interior designer, attended Marlborough College with the duchess.
Mr Van Cutsem is a childhood friend of Prince William, while Mr Baker went to St Andrews University with the duke and duchess.
Mr Lowther-Pinkerton served as private secretary to the duke and duchess and Prince Harry from 2005-2012, and is still principal private secretary and equerry on a part-time basis.
Mrs Samuel was a close friend of the duke's mother Diana, Princess of Wales, and is a trustee of charity Child Bereavement UK, which Prince William has supported.
Earl Grosvenor is the son of the Duke of Westminster.
The prince's parents, the Duke and Duchess of Cambridge, will be joined by family and close friends for the christening at the palace's Chapel Royal.
The Queen and Duke of Edinburgh will attend along with the Prince of Wales, the Duchess of Cornwall and Prince Harry.
The Duchess of Cambridge's parents Carole and Michael Middleton and siblings Pippa and James are also expected to be at the ceremony, along with the godparents and their spouses.
Celebrity portrait photographer Jason Bell will take the official pictures, and after the christening he is expected to capture a historic image of the Queen and three future monarchs - Princes Charles, William and George - together.
This will echo a 1894 picture from the christening of the future Edward VIII, showing him with his father, grandfather and great-grandmother - George V, Edward VII and Queen Victoria.
Previous royal babies including the Queen and princes Charles and William were christened at Buckingham Palace, but the duke and duchess have chosen the Chapel Royal - where Princess Diana lay before her funeral.
Prince George will wear a replica of the intricate lace and satin christening gown made for Queen Victoria's eldest daughter, Victoria, the Princess Royal, in 1841.
The gown was made by the Queen's dressmaker, Angela Kelly, and guests at the christening will be served cake taken from a tier of the duke and duchess's wedding cake.
According to the Church of England, godparents must be baptised themselves and should help children think about the "bigger questions" in life such as faith and love.
They are not expected to care for the child should anything happen to the parents.