The Duchess of Cambridge's younger sister Pippa Middleton has welcomed her third child, a little girl, with her husband James Matthews – brother of former Made in Chelsea star Spencer Matthews.
MORE: Pippa Middleton's new baby girl's sweet connection to cousin Prince George
Pippa, 38, who is also a mother to son Arthur, age three, and daughter, Grace, one, kept details of her third pregnancy very quiet. In fact, we only realised that Pippa was expecting when she debuted her bump at the Queen's Platinum Party at the Palace celebrations in June.
WATCH: Pippa welcomes baby Arthur
Pippa was equally private about the births of her elder two children, although we do know that she chose to welcome her son and daughter at London's St Mary's Hospital – the same place that her royal sister Kate gave birth.
Pippa and James were married on 20 May 2017 at St Mark's Church in Englefield, Berkshire which is close to her parents' home. Her niece Princess Charlotte and nephew Prince George were a bridesmaid and page boy at the happy occasion.
Here, we take a look back at the births of Pippa and James' three children…
The birth of Pippa Middleton's son Arthur
Pippa and her husband James welcomed their first child, Arthur Michael William Matthews, on 15 October 2018 at St Mary's Hospital's Lindo Wing.
A spokesperson told HELLO! at the time: "James and Pippa have had a baby boy. He was born Monday 15th October at 1.58pm, weighing 8lb and 9oz. Everyone is delighted and mother and baby are doing well."
Arthur's middle names are thought to pay tribute to members of the family – Michael is Pippa's father's name and was also the name of James' younger brother who tragically died in 1999 while climbing Mouth Everest.
MORE: Duchess Kate's birth stories of her three children George, Charlotte and Louis
Pippa while expecting Arthur
A few days prior to Arthur's birth, Pippa was seen attending Princess Eugenie and Jack Brooksbank's wedding in Windsor. The expectant mother looked glowing in a green, long-sleeved dress with a matching hat. She was joined by her husband James and her brother James Middleton.
Pippa's pregnancy was revealed in April, around the same time that her sister Kate gave birth to her third child, Prince Louis.
Shortly after the happy news was revealed, Kensington Palace said in a short statement: "The Duke and Duchess of Cambridge are thrilled for Pippa and James."
LOOK: Pippa Middleton and James Matthews' £17million London mansion is fit for royalty
Sisters Kate and Pippa Middleton
Pippa confirmed the news herself in June in her Waitrose Magazine fitness column, writing about her first trimester. She revealed: "I was lucky to pass the 12-week scan without suffering from morning sickness. That meant I was able to carry on as normal."
She also wrote: "When I learned the happy news that I was pregnant I realised I needed to adjust my normal four to five-day-a-week routine and find a way of continuing my exercise safely throughout the three trimesters. So, the journey of pregnancy fitness began."
Pippa - who is known for her love of sport – added that she continued to play tennis, saying: "I've been a tennis fan since childhood, as player and spectator, and have been keen to continue playing safely throughout pregnancy."
"Take Serena Williams - she famously proved that women can play a high level of tennis from two months (when she won the 2017 Australian Open) up to eight months."
The birth of Pippa Middleton's daughter Grace
Pippa and James welcomed their second child, Grace Elizabeth Jane, on 15 March 2021 at around 4.22am, weighing 6lbs 7oz. A family source told HELLO!: "Mother and baby are doing well. She's perfect, everyone is overjoyed at such a happy arrival."
Grace is the fifth grandchild of Pippa's parents Carole and Michael Middleton, and another cousin for Prince William and Kate's three children, Prince George, Princess Charlotte and Prince Louis.
Pippa and James' beautiful wedding day
The baby girl's middle names are a sweet tribute to her grandmothers Jane Matthews and Carole Elizabeth Middleton. Perhaps the name is a nod to royal relation Queen Elizabeth too!
Shortly after the birth, Carole was seen arriving at Pippa and James's five-story townhouse to help with baby duties. Carole will no doubt have loved meeting her new grandchild so soon and lending a helping hand to Pippa with her newborn and toddler Arthur.
The Middleton family (from L-R Michael and Carole, James and Pippa, James Middleton)
Pippa kept relatively quiet during her second pregnancy and was only spotted out and about a handful of times, walking in her exclusive West London neighbourhood.
The birth of Pippa Middleton's new baby girl
According to PEOPLE, Pippa gave birth to her daughter at the end of June, just weeks after attending the Queen's Platinum Jubilee Concert at Buckingham Palace.
As yet, no details are known of her new daughter's name or birth weight, or if Pippa had her baby at St Mary's Hospital as she did with Arthur and Grace.
Pippa shortly before the birth of her third child
We did wonder whether Pippa had welcomed her third child when she missed this year's Wimbledon tennis championships in late June, early July. The columnist is an avid tennis fan who rarely misses the opportunity to soak up some world-class sport from the Royal Box.
Duchess Kate was also noticeably quiet with her royal engagements during the week of 27 June – perhaps helping her sister with her newborn?
Just recently, Pippa spoke of her family life as she completes her Master's degree in Physical Education, Sport and Physical Literacy at the University of Wales Trinity Saint David. She studied how parents can encourage movement in their pre-nursery children.
In a statement from the university, Pippa said: "I have enjoyed the balance of work and motherhood and getting back into reading, writing, and learning again."
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