A statement posted to the couple's official social media accounts on Sunday evening shared Charles and Camilla's joy. It read: "Congratulations to Harry, Meghan and Archie on the arrival of baby Lilibet Diana [confetti emoji]. Wishing them all well at this special time."
Earlier in the day, Buckingham Palace released a statement on behalf of the Queen and the senior royals.
It read: "The Queen, The Prince of Wales and The Duchess of Cornwall, and The Duke and Duchess of Cambridge have been informed and are delighted with the news of the birth of a daughter for The Duke and Duchess of Sussex."
WATCH: Prince Harry and Meghan's son Archie makes adorable cameo appearance
The Sussexes' spokesperson confirmed the birth in a statement that read: "It is with great joy that Prince Harry and Meghan, The Duke and Duchess of Sussex, welcome their daughter, Lilibet "Lili" Diana Mountbatten-Windsor, to the world.
"Lili was born on Friday, June 4 at 11:40 a.m. in the trusted care of the doctors and staff at Santa Barbara Cottage Hospital in Santa Barbara, CA. She weighed 7 lbs 11 oz. Both mother and child are healthy and well, and settling in at home.
"Lili is named after her great-grandmother, Her Majesty The Queen, whose family nickname is Lilibet. Her middle name, Diana, was chosen to honor her beloved late grandmother, The Princess of Wales.
Meghan and Harry are already doting parents to two-year-old Archie
"This is the second child for the couple, who also have a two-year-old son named Archie Harrison Mountbatten-Windsor. The Duke and Duchess thank you for your warm wishes and prayers as they enjoy this special time as a family."
Harry and Meghan's daughter is now eighth-in-line to the British throne after her big brother Archie, who turned two in May, as well as her dad Harry, her cousins Prince George, Princess Charlotte and Prince Louis, her uncle Prince William, her grandfather Prince Charles and of course, the Queen.
The Duke and Duchess of Sussex had previously revealed they were having a girl during their highly publicised interview with Oprah Winfrey back in March.
After Oprah asked the couple if they knew the baby's gender, Meghan sweetly looked at her husband, nodded and told him, "You can tell her." "No, go for it," Harry said, as his wife insisted, "No, no." "It's a girl!" Harry proudly said, throwing his arms into the air and exclaiming, "Yeah!"
Meghan pictured chatting to Charles when she was pregnant with Archie
While Harry spoke about his strained relationship with his father Charles during the Oprah interview, the future King will no doubt be delighted to welcome another grandchild and will be thrilled for his younger son.
Charles is already the proud grandparent of Archie as well as his royal cousins, George, Charlotte and Louis, who affectionately call him 'Grandpa Wales'.
Camilla, meanwhile, has five grandchildren from her first marriage to Andrew Parker Bowles. The ex-couple married in 1973 and had two children, Tom Parker Bowles and Laura Lopes.
Laura has three children, Eliza, and twins Gus and Louis, while Tom has two children, Lola and Freddy.
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