The 56-year-old revealed on Twitter that he had received a "touching" gift from one of Diana's fans – a bouquet of flowers and a sweet note to mark the poignant day.
Posting a photo of the handwritten card laying on top of brown paper, which had white flowers peeking through, Charles wrote: "Received at @AlthorpHouse today - amazing, and touching."
Charles Spencer was touched by this thoughtful gift on Princess Diana's birthday
The card read: "Happy Birthday Diana, Princess of Wales. I will always remember you. From the lady who lives near Heathrow. From Vanessa."
Charles' followers were equally as touched by the thoughtful gift, with one commenting: "That's so beautiful and touching. Diana will always remain as the Queen of Hearts." A second wrote: "That is very sweet, she’s remembered kindly by so many. No doubt a poignant day for you. Sending you best wishes."
"The irreplaceable Diana. She will always be loved. She will always be beautiful. Thank you for sharing. That's very touching. I hope you're ok today Charles. Take care," a third added.
Princess Diana would have been 59 on 1 July
Lady Diana Spencer was the youngest daughter of John Spencer, 8th Earl Spencer and Frances Shand Kydd. The nursery teacher's assistant married Prince Charles at St Paul's Cathedral in 1981 and the couple welcomed two sons, Prince William and Prince Harry, in 1982 and 1984 respectively. Charles and Diana's marriage broke down and the pair had separated by 1992, finalising their divorce in 1996.
Diana was renowned for her charity work and was patron of over 100 organisations before her divorce, working with the homeless, youth, drug addicts, and the elderly. She campaigned against the use of landmines and fought to reduce the stigma around HIV/AIDS. The Princess was also known for her incredible sense of style and her public charisma.
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