The Duchess of Cambrige's sister, 35, welcomed her baby boy weighing 8lb and 9oz at the private Lindo Wing, at St Mary's Hospital, Paddington, last month but at the time his name had been kept under wraps.
The inspiration for his other middle name is thought to be from the new mum's brother-in-law Prince William.
Michael is thought to be a tribute to both Middleton's father and James Matthews' late brother, Michael, who died in 1999 at just 22 years old while climbing Mount Everest, according to the Mail.
James' younger brother Spencer also chose Michael as the middle name of his newborn son Theodore.
Rumours surfaced in April 2018 that Pippa was pregnant, shortly before Kate Middleton gave birth to Prince Louis.
On October 16, Middleton gave birth to a son just three hours after arriving at hospital.
Arthur will be first cousins with royals Prince George, Princess Charlotte and Prince Louis, along with Prince Harry and Meghan Markle's future baby.
"James and Pippa have had a baby boy", it read.
Kate and husband Prince William were clearly over the moon for Pippa and James with a statement from Kensington Palace reading: "The Duke and Duchess of Cambridge are thrilled for Pippa and James".
But the news wasn't made public until October 16, followed by a statement from Pippa's older sister, Kate Middleton, and brother-in-law, Prince William, saying they are "thrilled" for the couple.
On baby Arthur's birth certificate mother Pippa Middleton's profession is also listed as author.
Related News:
-
Apparent Nazi Salute In US High School Prom Photo Prompts Outrage
The Baraboo School District says the photo wasn't taken on school property or at a school-sponsored event. "Bullying. More than 50 boys from Baraboo High School in Wisconsin were pictured making the "Sieg Heil" gesture.Intel unveils XMM 8160 5G modem for a 2H 2019 arrival
It will come with EN-DC too, which will allow this modem to support 4G and 5G networks simultaneously. Some earlier reports suggested that MediaTek is working on 5G modem for lower priced devices.Trump’s motorcade to cemetery would have disrupted roads, White House says
The White House on Monday confirmed that President Donald Trump will not visit Arlington National Cemetery on Veteran's Day. Trump is attending centennial commemorations in Paris this weekend to mark the Armistice that ended World War I. -
Liverpool man could face lengthy suspension after charge from the FA
According to the Daily Mail , the FA have already conducted an eight-month investigation before announcing the misconduct charge. The England worldwide has been given until 18:00 GMT on Tuesday, 20 November to respond to the charge.Trump Blames Secret Service For Missing WWI Ceremony Because Of Rain
Also known as the Belleau Wood cemetery, the site is home to the graves of 2,289 American war dead and 1,060 names of the missing. He wrote: " Emmanuel Macron suggests building its own army to protect Europe against the US, China and Russian Federation ".This year's I'm A Celebrity line-up
Made in Chelsea star Georgia "Toff" Toffolo was the victor of the 2017 edition of the show and this year's line-up includes a famous football manager, an X-Factor runner-up and a former soap star. -
Fallout 76 release date countdown: Launch times, review scores, cheapest prices, more
With a final install size of 51 gigabytes, only 0.0048% of the game is actually on the disc you buy. The Xbox One and PS4 versions will still be available through their respective stores.The new ‘Game of Thrones’ season will premiere in April 2019
Game of Thrones fans have been waiting to find out when the final season of their favorite fantasy series will finally arrive. On Twitter , HBO released a teaser for the final season with the text "Every battle".Flipkart CEO Binny resigns, quits immediately
Binny Bansal had co-founded Flipkart with his Indian Institute of Technology-Delhi batchmate Sachin Bansal a decade ago. This is published unedited from the PTI feed . "It did, however, surface a lack of transparency on Binny's part". -
Arsenal give positive update on Welbeck injury status
The 27-year-old was injured during Thursday's Europa League draw with Sporting Lisbon, and had to be carried off on a stretcher. Welbeck posted an image of himself giving a thumbs up on Instagram on Tuesday afternoon.Black Ops 4: How to Unlock Nikolai in Blackout
Hardcore multiplayer modes were also given a balance update to make SMGs more competitive. The map will be available for free and does not require the purchase of a Black Ops pass.Security guard, 26, is killed by a police officer in Chicago
Officers from Robbins, Illinois, and the nearby village of Midlothian were responding to reports of shots fired after 4 a.m. Jemel was a gifted basketball player and musician, and his love for God and his family were at the forefront of his life.