What's the most embarrassing news you've had to give someone else?

I worked at a veterinary hospital and had a dog owner call me to complain about a charge on her credit card. The card showed a charge for $100 on a day that she had been to our office but she swore she paid cash. I looked all through our transaction records and did not show us having run her card at all. She then said that it was also strange that the charge had showed up with the name of the business as the "Highliter Club" instead of our business name. The Highliter Club is a strip club in our city with full nudity. She was a very old woman and I was about to tell her this when she added, "well my son has a card connected to this account also, so maybe I should ask him". I couldn't bring myself to tell her what it was because it would have been so embarrassing. I'm sure she felt it when she found out from her son.

Anyone else had a situation where they had to deliver embarrassing news?