Among the first to meet the new arrival was Middleton's sister, Pippa Middleton, who was spotted arriving at Kensington Palace on Tuesday, April 24.
Pippa made her way to the palace in a pink turtleneck sweater and pink coat, her visit making her one of the first official visitors to the new prince, whose name has not yet been announced.
Prince Harry and Meghan Markle are also expected to be some of the first to meet the infant. Prince Charles returns from Anzac Day commemorations in France on Wednesday, and Queen Elizabeth is currently staying at Windsor Castle with husband Prince Philip, who is recovering from hip surgery.
The newborn's birth was announced on Twitter by Kensington Palace, with a statement sharing that William was present for the birth and that Middleton was doing well.
Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 1101hrs.
The baby weighs 8lbs 7oz.
The Duke of Cambridge was present for the birth.
Her Royal Highness and her child are both doing well.— Kensington Palace (@KensingtonRoyal) April 23, 2018
The couple's older children, Prince George and Princess Charlotte, later visited St. Mary's Hospital to meet their younger brother, leaving for Kensington Palace soon after.
William, Kate and their new son left the hospital Monday evening, with the palace sharing a statement of thanks on Twitter.
"Their Royal Highnesses would like to thank all staff at the hospital for the care and treatment they have received," the statement read. "They would also like to thank everyone for their warm wishes."
Their Royal Highnesses would like to thank all staff at the hospital for the care and treatment they have received. They would also like to thank everyone for their warm wishes.— Kensington Palace (@KensingtonRoyal) April 23, 2018
Pippa is also rumored to be pregnant with her first child with husband James Matthews, with reports surfacing just days before Kate went into labor.
"When Pippa found out she was pregnant, she was obviously thrilled and utterly overjoyed," a source told The Sun. "Naturally, big sister Kate and parents, Carole and Michael, were the first people she told — James aside — and they could not have been more delighted.
Pippa and Matthews wed in May 2017 after getting engaged in summer 2016.
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