The Duchess of Cambridge gave birth Monday to her first child, an 8-pound, 6-ounce boy at 4:24 p.m. local time (11:24 a.m. ET).
The palace revealed the news via press release at 8 p.m. local time following a hospital stay that lasted more than 14 hours at London's St. Mary’s Hospital, the same facility where Princes William and Harry were born.
The baby's birth was to be announced to the world in a formal declaration placed in front of Buckingham Palace on an easel, the same one used to announce Prince William’s birth 31 years ago. But the palace released the news to the media first; the formal notice was posted a few minutes later.
"Her Royal Highness and her child are both doing well and will remain in hospital overnight," the statement read.
"We could not be happier," new dad Prince William said via his spokesman.
The name of the baby, the palace said, will be announced "in due course." Prince William's parents, Prince Charles and Princess Diana, took a week to announce his name.
The infant will be third in line to the British throne, after his father and grandfather, Prince Charles. He is the first grandchild for both Prince Charles and the Middleton family.
“Both my wife and I are overjoyed at the arrival of my first grandchild," said Prince Charles in a statement. "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."