Click through to see the baby's first moments in public with the Duke and Duchess, and read below for everything you need to know about the birth of Britain's newest royal heir, updated LIVE:
3:10 pm EST: Prince Harry on meeting little Prince George: "It's fantastic to have another addition to the family," though he joked "I only hope my brother knows how expensive my baby sitting charges are." He said that his role as an uncle will be "to make sure he has a good upbringing, and keep him out of harm's way, and to make sure he has fun." As if we needed to love him even more!
1:20 pm EST: It was announced by Clarence House that the baby's name is George Alexander Louis, and he will be known as His Royal Highness Prince George of Cambridge!
1:10 pm EST: We are told the Royal Baby's name will be announced within the next 15 minutes.
10:35 am EST: A Kensington Palace spokesperson said today of the Cambridges: "This is now private and quiet time for them to get to know their son." So we will wait until they decide on a name -- and decide to let us know. We hope they're enjoying their newest addition in peace today, with the Middleton family.
8:36 am EST: Kate and William take baby Cambridge on his first road trip! After a meet and greet with the Queen, they're off to visit grandparents Carole and Michael Middleton at their home in Bucklebury.
Photo Credit: Rex USA
6:39 am EST: Queen Elizabeth II has visited the Prince of Cambridge and his proud parents at their Nottingham Cottage in Kensington Palace, spending a little over 30 minutes with the new family. Many are reporting that Will and Kate planned to discuss possible names with the 87-year-old Queen. The Prince of Cambridge is the third in line to the throne.
Since coming home with his parents, the Prince of Cambridge has also met his uncle Prince Harry and Aunt Pippa.
Photo Credit: Rex USA
4:55 pm EST: A very popular baby! Peter Hunt of the BBC reports a staggering number of people who were talking about the Prince of Cambridge when Kate and William presented him to the public:
3:05 pm EST: Spotted by many watching the baby's first moments in the spotlight, the little Prince already has his regal wave down pat! Check out the clip from Twitter user @DiannaMcD:
2:22 pm EST: William said that the baby has "a set of lungs on him." Kate said: "It's very emotional, it's such a special time. I think any parent will know what this feeling feels like." The couple put the Prince into the car, and Wills drove them home to Kensington Palace. Click through the gallery above to see more photos from the new family's first public moment together!
Photos Credit: AP
2:12 pm EST: Kate and William have exited St. Mary's Hospital after saying goodbye to senior medical staff. They are standing on the steps of the Lindo Wing to present the Prince of Cambridge to the world and will answer few questions from the press. Kate wore a baby blue bespoke polka-dotted Jenny Packham (her favorite!) dress and looked gorgeous. When asked who he looks most like, William said "he's got her looks, thankfully!"
See Kate's lovely pregnancy style here.
2:00 pm EST: 5 minute warning from Kensington Palace!
1:10 pm EST: Kensington Palace has confirmed that the Duke and Duchess of Cambridge will leave the hospital "later this evening." It's currently just after 6pm in London.
An official statement from the palace: "Their Royal Highnesses would like to reiterate their thanks to the hospital for the care and treatment they have all received. Her Royal Highness The Duchess of Cambridge will be discharged this evening from St. Mary's Hospital, Paddington," and will return home to Kensington Palace.
12:55 pm EST: Charles and Camilla exited the hospital with big grins, delighted with the royal baby. Charles spoke with press, saying "just wait and see in a minute!" STAND BY.
12:30 pm EST: Charles and Camilla have arrived to visit the new Prince! Charles asks the press, "Have you had a long wait?" The Prince of Wales was met at the Lindo Wing entrance by William's private secretary, Miguel Head.
Photo Credit: AP
12:25 pm EST: Lots of commotion outside the entrance to the Lindo Wing -- are they on their way out or are Charles and Camilla possibly en route?
11:42 am EST: According to London-based blogger The Madam Editor, the line for taking a photo of HRH The Prince of Cambridge's birth announcement is quite a wait...
11:15 am EST: Carole and Michael Middleton have just left the hospital and stopped to speak with the press. Of their visit with their daughter and new grandson, Carole said that Kate and her son are "both doing really well," and that "he is absolutely beautiful, we are thrilled." She gushed that they had a "wonderful first cuddle." When asked if they have any name suggestions, she laughed, "absolutely not!"
Carole was wearing the £335 Orla Kiely 'Dancing Girls' tea dress in pebble -- a lovely choice to visit her grandson. Congrats to the new grandparents!
Kate is a fan of Orla Kiely, too! See her best fashion statements here.
10:15 am EST: Time to meet their grandchild! Carole and Michael Middleton are visiting their daughter in St. Mary's Hospital.
Photo Credit: Peter Macdiarmid/Getty Images
9:47 am EST: Royal Police were seen delivering two pizza pies to the rear of St. Mary's Hospital -- Kate definitely deserves some pizza after giving birth to the next King of England!
9:00 am EST: A 62-gun salute is being fired off in honor of Britain's newest Prince at the Tower of London in a customary salute, and the bells of Westminster Abbey are ringing out for the baby, and will continue to ring for 3 hours as celebrations continue.
7:00 am EST: The Duke and Duchess made an official statement of thanks: "We would like to thank the staff at the Lindo Wing and the whole hospital for the tremendous care the three of us have received. We know it has been a very busy period for the hospital and we would like to thank everyone - staff, patients and visitors - for their understanding during this time."
Kensington Palace said that "Mother, son and father are all doing well this morning," and that they'll likely depart the Hospital this evening (but not before 6pm BST) or tomorrow morning. We can't wait!
5:00 am EST: Kate's hairdresser has arrived (as has a carseat for the new Prince)! Will they be heading home soon?
5:30 pm EST: A statement has been released from the President of the United States, congratulating the Duke and Duchess of Cambridge:
5:00 pm EST: Said the Duke of Cambridge of his newborn son, "We could not be happier." He will stay the night in the hospital with his wife and baby boy.
3:58 pm EST: The Prince of Wales said of the news: "Both my wife and I are overjoyed at the arrival of my first grandchild. It is an incredibly special moment for William and Catherine and we are so thrilled for them on the birth of their baby boy.
Grandparenthood is a unique moment in anyone's life, as countless kind people have told me in recent months, so I am enormously proud and happy to be a grandfather for the first time and we are eagerly looking forward to seeing the baby in the near future."
3:30 pm EST: The announcement we've all been waiting for! Kate and William have welcomed a baby BOY! He was born at 4:24 pm BST, weighing 8lbs. 6oz. Congrats to the new parents!
3:01 pm EST: According to BBC News reporter Peter Hunt, "Ken Palace have changed their plans. The first we will know about the baby will be when they release a formal press release.
2:40 pm EST: Prince Charles has commented on the impending birth of the Royal Baby, saying that the crowd will "probably know more about [the baby] than I do," and that he is "very grateful indeed for the kind wishes for my rather slowly-approaching grandfatherhood."
12:43 pm EST: According to the Telegraph, "America is now the biggest global contributor on social media, followed by the UK and then Canada and Australia." We feel it's likely due to the time difference, but just further proof that Royal Baby fever in the U.S. is at extremely high temperatures!
12:11 pm EST: BBC New reporter Peter Hunt reveals via Twitter: "We'll know a baby has been born when one of Kate's officials emerges from the Lindo Wing with a medical bulletin in their hands #RoyalBaby" and that the official will be Ed Perkins, the press secretary for the Duke and Duchess.
12:00 pm EST: As reporters continue to pass the time outside the Lindo Wing, BBC's Simon McCoy gives a very frank and honest report: they don't know anything.
11:20 am EST: David Cameron, Prime Minister of Great Britain said he's in no position to give the Duke and Duchess of Cambridge advice on the birth, but that they should "enjoy and savor every moment." He added: "As a man who has been present at four births and hasn't really had to do anything other than greet the lovely arrival and give it a cuddle, I'm not really in a position to advise on childbirth."
Photo Credit: Paul Rogers - WPA Pool/Getty Images
11:05 am EST: A police officer accidentally shows off the confidential briefing of the security plan for the Duchess's stay at the hospital, right in front of the world's photographers. This has raised fears that the plan has been compromised, and all are on high alert.
10:40 am EST: The Queen arrives in a black Range Rover to Buckingham Palace from Windsor where she was staying while on vacation.
Photo Credit: Justin Tallis/AFP/Getty Images
8:14 am EST: A black Range Rover used by the Palace's Security team has arrived at the Mary Stanford entrance -- used by the Duchess of Cambridge as well as Princess Diana when pregnant with William -- to drop off a laptop and iPod. Are Kate and Wills bored?
8:00 am EST: Every morning show, on all the major networks began their broadcast with the royal baby coverage.
1:00 am EST: Shortly after 1am (6am BST), news broke the Duchess of Cambridge was admitted to St. Mary's Hospital in Paddington, London.