The night before their wedding in 1981, King Charles sent some kind, wise words of encouragement to his wife-to-be, along with a sentimental gift. The-then Prince of Wales married Lady Diana Spencer at St Paul's Cathedral on July 29, 1981 in a ceremony which was widely dubbed the "wedding of the century".
According to journalist Andrew Morton's book, Diana: In Her Own Words, Diana reportedly said: "He sent me a very nice signet ring the night before to Clarence House, with the Prince of Wales feathers on and a very nice card that said: 'I'm so proud of you and when you come up I'll be there at the altar for you tomorrow. Just look 'em in the eye and knock 'em dead.'"
Diana was pictured wearing her special gift on several occasions, including to the Regent Street Christmas lights switch on later that year.

The lavish affair was broadcast and watched by 750 million people in 74 countries around the world.
Their extravagant wedding was seemingly a dream come true for the bride. "I remember being so in love with my husband that I couldn't take my eyes off him," Diana also told Mr Morton.
She added: "I just absolutely thought I was the luckiest girl in the world. He was going to look after me."
Diana's gown, which was crafted in the space of three months, was made with ivory silk taffeta, and had a 25-foot train.
Florist David Longman revealed that after Queen Elizabeth lost the flowers during her own wedding, she started the tradition of having two identical bouquets made to prevent a similar mishap. "We made two bouquets," head florist David Longman said. "The first one had to be delivered at 8 o'clock to Buckingham Palace."
Longman created two identical bouquets for a very practical reason, so that Diana did not lose it.
"We had a police escort motorcyclist who took us all through the city to the Palace. Then we came back, and by that time they had finished the second bouquet and back we went again."
The bouquet featured gardenias, stephanotis, odontoglossum orchid, lily of the valley, Earl Mountbatten roses, freesia, veronica, ivy, myrtle and tradescantia.
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