Willow, 3, shares crisps with Prince William

Prince accepts the crisp in question while thanking little Willow

When Prince William paused to greet three-year-old Willow during a visit to the Royal Cornwall Show, her family never expected a gift to exchange hands.

They were taken aback when Willow reached up with a single Quaver - and even more surprised when the prince popped the savoury snack into his jacket pocket.

"I don't think I've ever been offered a Quaver before," the prince said. "I'm going to save this and put it in my pocket for later."

Grandmother Sharon Hart, who captured the moment on video, told the BBC: "It was a lovely genuine moment and a memory that we will never forget."

Ms Hart, from Luxulyan, Cornwall, said: "I guess he gets some very expensive presents and this was a first.

"Willow always wants to be a princess, so the fact she met a real live prince - she thought that was incredible."

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The Prince of Wales visited the Royal Cornwall Show on Friday, where he toured the exhibits, spoke to visitors and sampled local produce, including Cornish Rattler cider.

Prince William, the Duke of Cornwall, is a patron of the Royal Cornwall Agricultural Association, the charity which organises the three-day show.

Willow was attending with her family, including brothers Jude, six, and Noah, eight.

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'Tight with her Quavers'

Ms Hart, 65, said: "He was leaving the Duchy tent when he passed us.

"We were just watching and hoping we'd get a glimpse when there was a commotion in front of us and before we knew it Willow was handing out a Quaver.

"She's usually quite tight with her Quavers so it obviously meant a lot to her.

"He was a real gent, he thanked her and told her he'd never been given a Quaver as a gift."

Jodie Hart, Willow's mother, said: "She's had another packet of crisps today and said she wanted to share them with Prince William.

"We told her he was probably a little busy."

Ms Hart added: "What a lovely man he is and what a gentleman - our grandchildren were thrilled to see him, never mind talk to him.

"He just made it so important, it was lovely. His humanity shone through."