Kensington Palace have confirmed Duchess Catherine has welcomed a son!
"Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 1101hrs. The baby weighs 8lbs 7oz. The Duke of Cambridge was present for the birth. Her Royal Highness and her child are both doing well," the palace confirmed in a statement.
News that Kate was in labour was first announced at 08:23am, London time, in a statement which said: "Her Royal Highness The Duchess of Cambridge was admitted to St. Mary's Hospital, Paddington, London earlier this morning in the early stages of labour."
"The Duchess travelled by car from Kensington Palace to the Lindo Wing at St. Mary's Hospital with The Duke of Cambridge."
Duchess Catherine has been accompanied to the Lindo Wing of St Mary's Hospital in Paddington, London by her husband Prince William, 35.
As confirmed by the palace, Kate actually went into labour several hours before they made the announcement.
Daily Mail royal reporter Rebecca English revealed Catherine was admitted to hospital before 6am UK time.
"I understand that the Duchess of Cambridge was admitted to the Lindo before 6am this morning - so I would expect an announcement sooner rather than later. She doesn't tend to hang around," she tweeted.
Meanwhile in yet another sign we could be seeing the couple imminently, the royal family's go-to photographer Chris Jackson has his camera ready to go for the moment the Duke and Duchess exit the hospital with their baby.
Chris Jackson's wife and Duchess Catherine's stylist Natasha Archer was also spotted leaving the hospital at around 10am, presumably to drop off the post-birth outfits Kate will step out in.
St Mary's is where the royal welcomed her two other Children, Prince George, four, and Princess Charlotte, two, and the private wing of the hospital provides all the security and comfort the Duchess will need.
With their past two children, William and Kate haven't officially announced the genders of George and Charlotte until after the birth. So we're guessing we won't know if we have a new prince or princess until baby Cambridge joins the world and the palace release an official statement.
Prince William and Duchess Catherine announced they were expecting their third child back in September, 2017.
"The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child," the palace said at the time.
"The Queen and members of both families are delighted with the news."
"As with her previous two pregnancies, The Duchess is suffering from Hyperemesis Gravidarum. Her royal highness will no longer carry out her planned engagement at the Hornsey Road Children's Centre in London today."
It concluded: "The Duchess is being cared for at Kensington Palace."
WATCH: Relive the moment they announced their baby news with the world. Post continues...
Prince William and Duchess Catherine are delighted to be having three children and have previously said their addition of their new bub is "very good news."
While many royal watchers predict they won't stop at three.
"There will be one more! There'll be four, they want four and there'll be four babies for William and Kate," former royal butler Paul Burrell told Now to Love in March.
Kate herself is one of three kids and has often spoken of the joys of having loving siblings around.
Despite their royal status, the Duke and Duchess of Cambridge are determined to give their growing family the most normal upbringing possible.
"We hope to encourage George and Charlotte to speak about their feelings, and to give them the tools and sensitivity to be supportive peers to their friends as they get older. We know there is no shame in a young child struggling with their emotions or suffering from a mental illness," Catherine has previously said of her approach to parenting.
"Stability at home is so important to me. I want to bring up my children in a happy, stable, secure world, and that is so important to both of us as parents," William explained to GQ last year.
"I want George to grow up in a real, living environment. I don't want him growing up behind palace walls, he has to be out there."
WATCH: Prince George and Princess Charlotte's cutest sibling moments. Post continues...
The new Prince or Princess will be fifth in line to the British Throne, bumping Uncle Harry to number six.
A huge congrats to the Cambridge clan!
Now to Love will be bringing you full coverage of the Royal Baby, live as it happens!