Prince William and the Duchess of Cambridge Welcome Baby Number Three

Baby boy arrives in a hurry.

The Duchess of Cambridge and her husband Prince William have welcomed baby number three -- a boy.

The couple travelled to the Lindo Wing at St Mary's Hospital, Paddington, in central London on Monday morning. The as-yet unnamed baby boy was born just hours later.

Prince William, Duke of Cambridge and Catherine, Duchess Of Cambridge outside The Lindo Wing with their new baby boy on April 23, 2018 in London, England. Image: Neil Mockford/Getty.

Kensington Palace confirmed in a tweet that both mother and baby were doing well and that Prince William was there for the birth -- although they revealed it in far more formal terms of course.

The royal announcement -- via Twitter. Most impressive birth announcement maybe ever.

The new prince officially arrived at 11:01 am Monday April 23 ( 8pm Eastern Standard Time) and weighed in at a healthy eight pounds, seven ounces. His name was not immediately announced as per royal tradition.

And now a mama of three. A relaxed and happy-looking Duchess of Cambridge holds her brand new baby boy. Image: Neil Mockford/Getty.

The baby boy, who will be fifth in line to the British throne and the Queen's sixth great-grandchild, has already met with his older brother Prince George and sister Princess Charlotte.

A serious-looking Prince George hand in hand with dad Prince William and a cheerful-looking Princess Charlotte. Image: Getty.

The siblings were clearly thrilled to be welcoming a new little brother, Princess Charlotte in particular who waved gleefully to the crowd of fans and well-wishers who had gathered outside the hospital.

Charlotte gives the crowd a cheeky wave hello before meeting her new baby brother. Image: Getty.

While it's traditional for the royals to present their baby to the public after birth, it's unlikely we will see much of the new addition in the coming weeks and months with both parents in the habit of carefully guarding their children's privacy.

Of course, we're likely to be treated with glimpses of the babe, plus official photographs of all special occasions. For now though we can share this darling image.

Brand new baby boy -- welcome to the world little one. Image: Getty.

Baby number three -- seen here in what looks to be the carriage from the the royal car seat -- is positively adorable with a sweet full mouth and the most adorable chubby cheeks. It's early days of course, but at this stage he bears a strong resemblance to his sister Princess Charlotte. Of course, only time will tell who he takes after physically and we will be watching and waiting and with great interest, not to mention pleasure.

What we don't have to wait to see is how cherished this child will be with both his proud father and glowing mother clearly smitten with their new addition. All you have to do is look at these images to almost feel their joy and why not - a healthy baby has been born and whether you're a royal or not, that's something akin to a miracle. All we can say is congratulations and well done. We can't wait to learn, hear and see more of your brand new boy child.