1. You understand that "Sorry I have rehearsals" is a valid excuse and doesn't mean you're being rude.
2. You know basically everything about each other, because you've played so many drama games together.
3. You know each other's routines for just before you go on stage.
4. You've experienced each other at your most tired and worn out, but you love each other regardless.
5. You know exactly how your BFF copes in any situation, because you've been through some pretty nerve-wracking times together.
6. You've done some pretty intense bonding during after-school and weekend rehearsals.
7. You have no qualms about getting changed in front of each other.
8. You've probably competed against each other for some of the same roles, and yet you still get excited about each other's successes.
9. You've helped each other out in lots of some sticky situations. Like when your BFF forgot to learn their lines by the deadline.
10. You've worn some pretty embarrassing costumes together.
And you didn't even bat an eyelid.