Madeleine's first babysitting job

How is it that my children....the offspring of an English teacher.....don't know how a library works? I'm rather ashamed to tell this story but it's funny and so I must. Today I decided to try out the story and craft time over at the Chino Hills Library. I was loading everyone into the car when I got the Quote of the Day:

Madeleine: "Are we going to Target?" - that speaks volumes, doesn't it?
Me: "No, we're going to the library"
Madeleine: "Why?"
Me: "To listen to stories and maybe pick out a couple of books"
Madeleine: "And buy them?"
Me: "No, we pick out books, we check them out with the lady and we bring them home for a week and then we have to bring them back but we can find new books.
She thinks.
Madeleine: "You mean we babysit them?"
I laugh.
Me: "Yeah, I gues we do. We are babysitting books for a week."
Madeleine (laughing): "Babysitting books. Now that's just silly!"
Lily: "That's just silly!"