My mom has fibromyalgia. It turns out she's had it most of her life and not known about it.
I still remember a very serious conversation the two of us had when I was in high school. She mentioned that cruise control is one of the most important things I should look for when buying a car. "Otherwise," she said, "you're going to have a real hard time driving for long distances when your leg starts to hurt really bad."
For the longest time, I worried about ever having to get behind the wheel and drive across a few states without cruise control. Only later, did I realize it was because she always hurts and didn't know why.