Pippa Middleton, the sister of Catherine, Duchess of Cambridge, has given birth to a baby boy.
On Monday, the 35-year-old was spotted checking into the Lindo Wing at St. Mary's Hospital in London, where the duchess welcomed all three of her children, and Middleton gave birth at 1:58 p.m. local time.
"Everyone is delighted and mother and baby are doing well," her representative tells People.com.
The child is Middleton's first with her husband James Matthews, who she wed in May 2017.
The tot arrived just three days after the new mother and father joined the duchess and her husband Prince William, the Duke of Cambridge, to attend the royal wedding of Princess Eugenie and Jack Brooksbank at Windsor Castle, England, on Friday.
A short statement issued by royal representatives at Kensington Palace reads: "The Duke and Duchess of Cambridge are thrilled for Pippa and James."
The newborn, whose name has yet to be released, will have playmates in Catherine's three children -- Prince George, 5; Princess Charlotte, 3; and Prince Louis, 5 months -- while William's brother Prince Harry is also preparing to become a dad. He and his wife, Meghan, Duchess of Sussex, announced their pregnancy on Monday, after landing in Australia for their first official royal tour together.
"Their Royal Highnesses The Duke and Duchess of Sussex are very pleased to announce that The Duchess of Sussex is expecting a baby in the Spring of 2019," a statement issued via social media read. "Their Royal Highnesses have appreciated all of the support they have received from people around the world since their wedding in May and are delighted to be able to share this happy news with the public."