A stranger gave a £10 gift voucher to a five-year-old girl – because she was so well mannered.
The mystery woman approached grandfather Anthony Roberts and his granddaughter Ruby and remarked on how polite, pleasant and well behaved the little girl was.
She then presented surprised Ruby with the gift voucher.
Anthony, a 62-year-old property developer, was taking Ruby to look at the toys in Argos on their way home from school.
He's now trying to track down the generous gift-giver - who approached the pair while Ruby was spelling out the names of the toys on her wish-list - but left before she could be thanked.
Ruby was able to buy the toy doll she had wanted, by combining the £10 voucher with the money she had saved taking out the rubbish at a family friend's holiday home.
Anthony, from Newquay, Cornwall, said: "I pick Ruby up from school occasionally and on the walk back one of the things we do is go into Argos and look at the screens to see what toys there are around.
"She has to spell out what she wants so we use it as an educational tool and pass away a quarter of an hour.
"A lady who had been watching Ruby came up and gave her a gift voucher after remarking how polite, pleasant and well behaved she was.
"Ruby did not know what it was at first until I explained that's what you get for being a nice person.
"I did not get the lady's name and she was gone before we could thank her properly.
"Maybe, without realising it, she has taught Ruby an important lesson about being a nice person.
"I think it was a genuinely moving thing to do because people do not do these sorts of things nowadays.
"There is an unfortunate flaw in our society whereby good deeds can often be misinterpreted. Even if you say 'hello' to someone you do not always get a reaction because they're scared you will do something.
"I later posted what had happened on Facebook and it got a tremendous response. I think people are pleased nice things happen."
The generous donation echoes the £5 gift and a note a stranger gave single mother Samantha Welch on board a train after being impressed by her parenting of her three-year-old son Rylan last month.
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