Here in NJ, there used to be (I don't think it exists anymore) a psychiatric hospital commonly referred to as Marlboro...from the town or township it was in, I think.
When I used to drive my mother to distraction, she'd tell me I was going to "Drive her to Marlboro". In my naive, little kid mind, I thought she meant that she was going to change cigarette brands.
A childhood belief about family

others believed things like this
- I used to believe that the "cruise control" button in cars meant that the car could drive/maneauver itself.— Myriam
- I thought the no overtaking sign meant that red cars cannot drive by black cars.— Helen
- I thought you were supposed to drive down the center of the road.— Cassiopeia
- I thought that cruise control was like autopilot i.e the car would just drive itself if you turned it on— Yqatuba
- For some reason I thought any 4X4 vehicle would pull a wheelie when switched into 2 wheel drive.— Richard Davies
- Because of cartoons, I thought that to drive you'd just turn the steering wheel back and forth constantly. — Mitsuki