Kate Middleton was admitted to the hospital for a “planned abdominal surgery” last week, but it wasn’t known to insiders ahead of Kensington Palace’s Jan. 17 announcement, royal experts suggested to Fox News Digital. 

“Just days before the announcement I spoke to sources close to the family and they gave no indication that anything was afoot,” royal expert Shannon Felton Spence told Fox News Digital following a People magazine report that said her surgery came as a surprise to those close to the royal family. 

“I believe the report,” Spence said, adding that the princess is “essential to the health and wellness of the monarchy. “On the human side of it, she is the mother to a future king. She is the partner to a future king. Catherine is the stability, normalcy, and warmth of the family for the next two generations. She is also an invaluable tool for the institution, as she is consistently ranked as one of the most popular members.” 

Christopher Andersen, author of “The King: The Life of Charles III,” suggested that the main reason the Princess of Wales might have kept her impending surgery quiet was for the sake of her three young children. 

“William and Catherine somehow define this really beautiful and hopeful vision of the future,” she told Fox News Digital. “You can’t recreate it because it’s authentic and natural. It is effortless. That is why they are so important to today’s monarchy. They inspire people to look forward instead of backwards.”