If you have an older sibling, you better hope you both don't get this teacher. Fogs are teachers who tend to judge people based on their family or their experience with a student's family. If your sibling was a hard-working student or was just really good in that teacher's class, they expect you to be the exact same way. If your sibling struggled in that class or was bad, the teacher expects you to be the exact same way. No matter what you do, your siblings talents and reputation is branded on you for the entire year which means that there's always some tense pressure whenever you go to class.