Prince William is one proud royal papa.
"We could not be happier," the new dad said Monday following the birth of his first child with Kate Middleton.
Their son, whose name has yet to be announced, was born at 4:24 p.m. (British Summer Time), a little more than 10 hours after the Duke and Duchess of Cambridge arrived at St. Mary's Hospital in London, with Kate already in labor.
William was present for the birth and, according to a Kensington Palace spokesman, he will be spending the night at the hospital with his wife and newborn son.
Clarence House, Will's official residence from 2003 until his marriage to Kate and still home base for new granddad Prince Charles and Camilla, Duchess of Cornwall, is welcoming both congratulatory messages via Google Plus regarding the royal baby's arrival and birth announcements for other children that share the little prince's July 22, 2013, birthday.
"Use our hashtag #WelcometotheWorld to tell us about any other new arrivals today—we would love to hear from you! #RoyalBaby," social media-savvy Clarence House tweeted, followed by, "Thank you for your #WelcometotheWorld tweets—keep them coming! We will read as many as we can and pull some into a @ClarenceHouse @Storify."
Charles said in a statement earlier today: "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."
You're telling us, sir!
Queen Elizabeth II and her husband, Prince Philip, were also said—in a short but sweet statement issued by a monarchy spokesperson—to be "delighted at the news of the birth of The Duke and Duchess of Cambridge's baby."