Prince William and Kate Middleton Leave Hospital With Baby Boy

The new parents left St. Mary's Hospital's Lindo Wing with the new baby boy.

July 23, 2013, 2:53 AM

July 23, 2013— -- The world has gotten its much-anticipated first glimpse of Prince William and Kate Middleton's new royal baby boy.

In line with royal tradition, the Duke and Duchess of Cambridge stepped out of the doors of St. Mary's Hospital's Lindo Wing in London today to pose for photographs amid the wild cheers of the crowd gathered outside.

A radiant Kate held the newborn in her arms. The day-old baby was swaddled in a white blanket and poked his hand out, as if to greet the world.

Kate wore a baby-blue polka dot dress with her long brown hair flowing around her shoulders.

The new mom then handed the 8-pound, 6-ounce baby boy to his beaming father.

"He's got a good pair of lungs. That's for sure," William told the crowd. " He's a big boy. He's quite heavy. We're still working on a name, so we'll have that as soon as we can."

"It's the first time we've seen him, really, so we're having a proper chance to catch up," a smiling William said.

"It's very emotional," Kate said. "It's such a special time. I think any parent will know what this feeling feels like."

"He's got her looks, thankfully," William joked.

Kate quickly laughed and responded, "No, no, no."

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As for the baby's hair, William quipped, "He's got way more than me, thank God."

Kate also said that William has already "done his first nappy," or changed a diaper.

Before heading back into the hospital, William said, "I will remind him of his tardiness when he's a little older because I know how long you've all been standing out here. I hope you guys can get back to normal now and we can look after him."

Minutes later, the new parents came back out with the baby in a car seat. William got in the driver's seat and Kate got in the back with the baby as they drove off.

The historic moment was captured by the hordes of photographers outside who have been camped out for weeks.

The royal heir's name has not yet been announced. His title will be His Royal Highness Prince (name) of Cambridge.

Kensington Palace announced in a news release that HRH the Duchess of Cambridge would be discharged today from the hospital.

"The Duke and Duchess of Cambridge and their son will travel home to Kensington Palace," the statement said. "Their Royal Highnesses would like to reiterate their thanks to the hospital for the care and treatment they have all received."

The baby enjoyed his first visit with his grandparents today.

Kate Middleton's parents, Michael and Carole Middleton, were the first to visit their new grandson at the hospital in London where the royal baby was born Monday. They spent a little more than an hour at the hospital.

As they left, Carole Middleton told reporters of her first grandchild and his parents, "He's absolutely beautiful and they're doing so well."

When asked whether she could reveal the baby's name, Middleton, 58, laughed and said, "Absolutely not!"

She said the new parents are doing "fabulously" and that the first cuddle with her new grandson was "amazing."

"It's all coming back," the mother of three said as she beamed with joy.

Kate, 31, is the oldest of her three children, followed by Pippa Middleton, 29, and James Middleton, 26.

Prince Charles and his wife Camilla, Duchess of Cornwall, also visited the hospital shortly after. They smiled and waved as crowds cheered and they made their way inside.

Upon leaving, Charles hinted that the family would be coming out soon, saying, "You wait and see you'll see in a minute."

Watch "The Royal Baby: Heir to the Throne," a "20/20" special TONIGHT at 10 ET.

The world had been eagerly awaiting the first glimpse of the third in line to the British throne.

Camera crews have been lined up across the street from the Lindo Wing for weeks, waiting for the money shot when Kate Middleton and Prince William emerge from the hospital with their 8-pound, 6-ounce newborn son. Officials said William, who was by his wife's side during the birth, also spent the night in the hospital.

The royal couple will raise their bundle of joy in apartment 1A of Kensington Palace, which has more than 20 rooms. It's also the same palace in which William grew up, noted for its ornate interior design and picturesque gardens.

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"I'm sure Kate will enjoy sitting out there with the newborn baby in the sunshine, and there's also apparently a rooftop garden as well in the palace and the views from that must be absolutely stunning," ABC News royal contributor Victoria Murphy said.

And it's at Kensington Palace where Queen Elizabeth is expected to meet her great-grandson for the first time. The baby is the queen's third great-grandchild.

Celebrations continued today with gun salutes by royal artillery companies to honor the birth. Riders in uniform trotted past the palace to Green Park, where six field guns fired 41 blank rounds.

London's landmarks, including the London Eye, lit up Monday in the national colors of red, white and blue, and the city had a party atmosphere with celebratory crowds gathering outside Buckingham Palace.

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The other important aspect of the royal baby that has kept the masses guessing is the name. When William was born in 1982, his parents didn't reveal his name until a week later. His father, Prince Charles, was a month old before his name was made public.

Business for bookies in the U.K. was booming Monday as thousands placed bets on the name, with the favorites being George, James, Alexander, Louis and Henry.

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"Never underestimate the British public's obsession with the royal family," spokesman Alex Donohue of British gaming company Ladbrokes told The Associated Press.

The company received about 50,000 bets after Kate went into labor, the AP reported.

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