Three siblings of the late Princess Diana were among those to first hear the joyous news about the newest addition to the royal family on Monday.
The Duke and Duchess of Sussex welcomed their first child, a baby boy, and made sure to let Prince Harry's aunts and uncle know right away when Princess Diana's younger son became a father for the first time.
The palace announced that Lady Jane Fellowes, Lady Sarah McCorquodale and Earl Spencer were "delighted with the news" after being informed about the birth, along with Queen Elizabeth and members of Prince Harry's immediate family.
Lady Jane Fellowes, 62, and Lady Sarah McCorquodale, 64, are the older sisters of Princess Diana, who died in a car crash in 1997. Charles Spencer, 9th Earl Spencer, 54, is Diana's younger brother.
Fellowes delivered a reading at the wedding of Prince Harry and the former Meghan Markle last year, with Diana's other two siblings also in attendance.
The new baby would've been Diana's fourth grandchild, joining the three children of Prince William and the Duchess of Cambridge. The new baby is the eighth great-grandchild for Queen Elizabeth II, the longest-reigning monarch in British history.
The Duchess of Sussex had Prince Harry and her mother, Doria Ragland, by her side when she gave birth to a 7-pound, 3-ounce baby boy at 5:26 a.m. Monday.
"It was amazing. Absolutely incredible. I'm incredibly proud of my wife. As every father and parent would ever say, your baby is absolutely amazing, but this little thing is absolutely to die for, so I'm just over the moon," Harry told reporters gathered on the Windsor grounds just outside the couple's home, Frogmore Cottage.
The new royal baby now becomes the seventh in line to the throne, behind his father; three cousins, Prince George, 5, Princess Charlotte, 4, and Prince Louis, who just celebrated his first birthday; Harry's brother, Prince William; and the baby's grandfather, Prince Charles.
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