The mother-of-three is a private person, and because she has no royal or celebrity roles, she is mainly in the limelight due to her sister's status, so she's able to keep her family life largely under wraps.
WATCH: Pippa and Kate's wonderful sisterly bond
It's highly unlikely that Pippa will release a picture of her new baby, as she hasn't done so with her other children, and she doesn't even have social media.
This is completely different to her sister, who regularly releases pictures featuring her three children, often sharing new portraits of them on their birthdays.
Pippa debuted her baby bump in June
Pippa even kept her pregnancy very quiet, with fans only realising that she was expecting when she debuted her small bump at the late Queen's Platinum Party at the Palace celebrations in June.
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 – so we can only assume baby Rose was welcomed there too.
Pippa is married to brother of former Made in Chelsea star Spencer Matthews, James Matthews and they share children Arthur, Grace and Rose. While occasionally, Pippa used to be spotted with her children out and about in London, Pippa and sister Princess Kate have both relocated from the UK capital to the countryside.
The Middleton sisters are very close
Pippa has purchased a beautiful Georgian mansion in Berkshire while Princess Kate, along with her husband Prince William and three have moved to Adelaide Cottage in Windsor.
Pippa's incredible new home features a whopping 30 rooms and around 150 acres of grounds that houses a walled garden and greenhouses, according to the Daily Mail's Eden Confidential.
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