Ah children, I personally like them myself although the bratty ones are a pain in the ass. Everyone has already made good suggestions but if you take him to see the new Harry Potter movie, rent the others first before going to see it and that at the very least will take a day or two because of their length. Transformers is also another good idea, maybe buy a super cheap game at a store so that if he possibly breaks it, it won't really be much of a loss. Maybe take him to the park and get some ice cream just do everything you can to make no lag in time so that he doesn't have the chance to fart around and mess something up.
If all else fails, put him in a box and ship him to the other side of the world.
Good luck though, I guess I'm fortunate to have never dealt with kids in my family who were complete brats. I sure do have some brats in my family that are well into their adulthood, so I've always been more partial and friendly to kids.
