When I was in college, I took a weekend road trip with three friends to visit one of their families. It was an old house in a small town, and her parents split us up for sleeping arrangements among a few different bedrooms. I ended up in a tiny room off the dining area by myself, but two of my friends had to bunk together.
We were all sitting in the kitchen enjoying a nice breakfast the first morning when someone asked how we had slept. One of my friends suddenly looked very concerned. She turned to her bunkmate and said, "I hate to tell you this, but I think you had a seizure this morning."
"What?!" said the roommate, who had no history of medical issues.
"Yeah. When I woke up, I looked over, and you were lying there asleep, but you were just kind of shaking."
There was a long moment of silence while we processed this information. Then the friend whose house it was asked a very pertinent question.
"Did you happen to hear a high-pitched whistle at about the same time?"
She considered it. "Yes!"
"OK, so that was a train passing by, not a seizure."
Epilepsy averted, we went back to our bacon and eggs. And somewhere amid all the laughter, I'm sure there was a sigh of relief.