lending a library card, the reprecussions

I got a letter from a collecting company that says I owe $43 of library fines. How pleasant don't ya think? Well it was all thanks to my lovely little brother who I happen to have taken to the library about 3 months ago because he was working on a project for school. I offered to help him find some books and then take him back home so he could finish. But how does he repay this lovely favor of mine? By not turning in the book when we returned all the other ones. So I was thinking what I could make him do for the money. Because of course he doesn't have any right now. Maybe I'll make him wash my car, or do my laundry, or do the dishes everytime I'm supposed to. I dunno. It should be interesting.