The document gives the full name of the latest member of the royal family as His Royal Highness Prince Louis Arthur Charles of Cambridge.
William and Kate‘s third child was born at the private maternity unit of St Mary’s Hospital, Paddington on Monday April 23 at 11.01am, weighing 8lbs 7oz.
The Duke, who is taking a period off following the birth of his son, signed the birth certificate earlier on Tuesday at Kensington Palace with current Westminster registrar Patricia Gordon.
Although the birth certificate may seem a formality, it can be a stressful job as found by previous Westminster deputy registrar Alison Cathcart who revealed she received death threats over her ‘messy handwriting’ on Prince George’s form in 2013.
Louis’ document has been typed up which may have been an attempt to avoid a similar situation.
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Prince Louis’ birth certificate (pictured) has been released this morning after being signed by proud father William
The Duchess of Cambridge gave birth to Louis last Monday. She is pictured here with Prince William presenting the child to the world outside the Lindo Wing at St Mary’s Hospital in Paddington
The certificate was of standard type and the parents identified their occupations as Prince and Princess of the United Kingdom, as they had done previously on George’s certificate, pictured
Both George and Charlotte’s birth certificates, pictured, were handwritten but Louis’ has been typed up
The Duke of Cambridge, pictured with the Duchess and Louis at the hospital, signed the birth certificate this morning
Louis’ birth was the couple’s third visit to the Lindo Wing, with George delivered there in 2013, left, and Charlotte in 2015, right
Louis’ document listed the date and place of his birth and also gave the full name of his father and mother.
Normally, parents have to attend a register office within 42 days of a child being born but in this case the deputy registrar went to Kensington Palace.
Westminster City Council Registrar, Patricia Gordon, said: ‘It has been a great honour to register, and formally welcome the latest addition to the Royal Family, Prince Louis Arthur Charles.
‘This follows a long history of Westminster City Council registering royal births, including Prince Louis’ siblings Prince George and Princess Charlotte.’
But Ms Cathcart found it a very different experience in 2013, after admitting she became ‘flustered’ when writing on the document while sitting next to Prince William at Kensington Palace.
In a 2014 interview with the Daily Mail, she said: ‘I got death threats. One person said their cat had better handwriting, someone called for me to be fired and someone even said I was illiterate.’
She added: ‘Let’s just say I had to have more than one attempt. What can I say? It was a very hot day and I was flustered and trying to fill this thing in with Prince William sitting beside me.’
But the experience did not put her off entirely, as she described it as the ‘highlight’ of her career and returned to the palace two years later to write Charlotte’s certificate – again by hand.
As reported by Mail Online, Louis’ name serves as a poignant tribute to Prince Charles’ beloved great-uncle, mentor and ‘honorary grandfather’, Lord Mountbatten, who was killed in 1979 when the IRA placed a bomb in his fishing boat.
Alison Cathcart, the registrar who filled out George and Charlotte’s certificates, revealed she received death threats over the Prince’s document because of her ‘messy handwriting’
Prince Louis’ name was officially revealed last Friday after fans and bookmakers waited five days for confirmation, with many other names being touted as contenders including Albert and Alexander.
It comes ahead of Princess Charlotte celebrating her third birthday on Wednesday.
The royal youngster, who is getting used to being a big sister to Prince Louis, turns three just nine days after the arrival of her baby brother.
Confident Charlotte delighted royal fans by waving and leading her father the Duke of Cambridge up the steps of the Lindo Wing when she was taken to meet her new sibling for the first time last week.
The princess, who is fourth in line to the throne, is now the Cambridges’ middle child.
The past year saw another big change for Charlotte when she started nursery school. She attends Willcocks Nursery School, close to her Kensington Palace home.
The Duke and Duchess named Louis (pictured with his parents) in tribute to Prince Charles’ beloved great-uncle, mentor and ‘honorary grandfather’, Lord Mountbatten, who was killed in 1979. Pictured right is Kate gazing adoringly at her newborn son
The release of the birth certificate comes just a day before Princess Charlotte’s third birthday. She is pictured here waving to the media as she went to meet her baby brother last week
Confident Charlotte, left, was seen waving to the crowds last week as she and Prince George, right, were taken to St Mary’s Hospital by father William
Charlotte is expected to take a starring role as flower girl or bridesmaid when her uncle Prince Harry marries Meghan Markle in just over two weeks’ time.
She has already been a bridesmaid for aunt Pippa Middleton, who wed last May.
The princess has a reputation for being feisty compared to her older brother Prince George.
Meanwhile revellers will be able to wet the royal baby’s head at the first pub named after the new royal.
Drinkers in Great Notley, Essex, will be able to pop a cork and celebrate his arrival when the watering hole opens next week
And brewers McMullen’s say they would be more than happy to welcome the happy couple if they wanted to bring the Royals to the alehouse for a celebration.
The Duke and Duchess of Cambridge will be able to have a mini pub crawl if they wanted – as it is just 20 miles from another of the Hertford-based firm’s bar’s named for Princess Charlotte, in Colchester.
The patriotic pub boasts the newest addition will allow families to enjoy the best of the ‘British summer’.
It got its name as work finished on the day the baby was born and today painters were finishing up work on the establishment’s sign.
Meanwhile a pub in Great Notley, Essex, pictured, has been named after the newest royal and will open next week
Brewers McMullen’s, which run the new pub, said it was tricky to choose a ‘timeless’ name and wanted to pay tribute to the baby Prince
A rocking horse toy, pictured left, and a picture tribute of Kate kissing Louis’ head are part of the decorations
Claire and Aaron Wood , general managers of The Prince Louis, said: ‘We are thrilled to be opening in McMullen’s newest pub, our team have commenced training and were excited as us to know the name of the baby and pub.’
The brewers have ploughed more than £1million in refurbishing the pub, which despite its regal name will give punters a humble offering of chicken, curry, and real ales.
Heydon Mizon , managing director, said: ‘It is quite tricky to cho