The mother of a sick child is hoping to track down the good Samaritan who left £25 on her car to cover a parking fine.
Mairi Holden, 35, left her pink Honda Jazz on a single yellow line outside the Royal Hospital for Sick Children in Edinburgh on Wednesday evening. But she unexpectedly had to stay the night with her four-year-old son Oscar, who had suffered a severe asthma attack, and forgot all about the car.
When she emerged the next morning, she found two parking tickets on her windscreen - but there was cash and a note left under one. "Pay it then forget it happened!" it read.
Mairi posted a photo of the note on Facebook yesterday. "Would love to find out who did this! I'm still in a lovely feeling of shock!! Please share – maybe I'll be able to get in touch with this beautiful person!" she wrote.
"I'm still overwhelmed at the kindness of it. I'll never forget it, and if anyone has any idea of who it could have been, or recognises the writing or note paper, please let me know, I'd love to be able to thank them!"
Her appeal on the social network has racked up over 100,000 shares - although her benefactor still hasn't come forward.
"I would like to see how one person's kindness can have a huge impact on the world so many other people's lives," she says. "Imagine when the anonymous stranger finds out just what has happened as a result of doing such a lovely thing!"
Oh, and Oscar? He's now fine, she says.
Earlier this month, we reported on how one woman in Leyland in Lancashire has been leaving lottery scratchcards and cash for people to find, or pre-paying for coffee for a random stranger in cafes - and there have been plenty of similar examples over the years.
Indeed, there's a growing movement to carry out such 'random acts of kindness', and even a website devoted to highlighting them. Last week, in fact, was designated Random Acts of Kindness week, and it's possible that Mairi's benefactor was simply running a week late - or maybe had just got into the habit of generosity.