The other day I went to pick Younger Daughter up at the bus stop. The conversation went like this:
Me: How was school? Did you have a good day?
YD: Yeah ... do you see this stuff on the back of your hand? It's called "vines"!
Me: Um ... I believe they're called "veins".
YD: No, they're vines! They wind around and around our whole body. They hold us together. We learned about in science class.
Me: Well, the way we learned it is they're called "veins", and they carry blood around your body.
She probably still thinks they're called "vines", but at the moment I'm too busy teaching her to read to worry about it much.