"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.
The Prince first met Ms Dunne in 2015 and then again in 2017. Last year during the Australian royal tour, Harry introduced his wife, former actress Meghan Markle to Daphne outside the Royal Opera House.
"I'm going to get my wife to come here and say hello," Harry told the royal fan. Meghan gushed: "I'm so happy to finally meet you, I've heard so much about you,” with Meghan adding: "Hopefully the next time we see you we'll have our little one with us."
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