The heartbreaking news comes days after the Duke of Sussex sent the war widow a touching birthday greeting.
See Harry's beautiful birthday message to Daphne from last week here..
The message read: "Dear Daphne, my wife and I send our warmest wishes to you on the occasion of your 99th birthday on Friday."
The card continued: "We hope you have a wonderful celebration surrounded by family and friends and that you've managed to escape hospital.
"Congratulations on reaching this important and impressive milestone before your centenary year next year. Happy Birthday Daphne.
"Best wishes, Harry and Meghan, the Duke and Duchess of Sussex," the message concluded.
See Daphne speak about her many royal encounters with the lovable Prince here..