The Duchess of Cambridge and Prince William have welcomed their first child, a son, PEOPLE confirms.
The news the world's been waiting for since Kate went into London's St. Mary's Hospital early Monday morning was revealed Monday afternoon, some four hours after the Duchess, 31, gave birth.
The message was delivered in a press release, stating that a son was born at 4:24 p.m., weighing 8 lbs., 6 oz. After about 14 hours of labor, Kate had a natural delivery.
With a broad smile the couple's press secretary Ed Perkins took the announcement to a waiting blue Jaguar to be whisked to the palace.
Kate and William wanted to spend a bit of time with their baby and make their phone calls. But William, 31, personally told the Queen, his father, Prince Charles and wife Camilla and brother Prince Harry.
The Queen and Duke of Edinburgh "are delighted" by the news.
Kate's parents were also called.
"It's been a wonderful day and everyone's delighted," says a palace source.
British Prime Minister David Cameron is also among those informed, along with other high-ranking officials.
The new prince is a "wonderful baby, beautiful baby," Dr. Marcus Setchell told the crowd outside the hospital.
The waiting crowds celebrated near St. Mary's. The theatrical presentation of the birth news continued when the official notice was placed on an easel on the Buckingham Palace forecourt. "Her Royal Highness and her child are both doing well," it read. A gun salute in the royal parks in London is expected to follow.
The new arrival is third in line to the throne, following the baby's father, William, and (first-in-line) grandfather, Prince Charles, 64. The public will get its first glimpse of the child when the couple leave the hospital in the coming days.
Kate's pregnancy was revealed on Dec. 3, 2012, when she was admitted to the hospital in London suffering from severe morning sickness.
William spoke of the couple's desire to have children when they announced their engagement in 2010. He told ITN they would get to planning after their wedding: "Obviously we want a family, so we'll have to start thinking about that." And he has since said that he wants two kids.