"Indeed. And I'd like to apologise for that." Said Luna, catching Celestia by surprise. "I was being very immature. Replacing your sisters lungs with whoopie cushions is hardly the behaviour of a princess." Luna sighed, rubbing her tired face-but her contrition was clear. Celestia could see that her tiredness had been more than just physical malaise, now-guilt had been weighing her down. "I hope you can forgive me for my foalish actions. If you wish to prank me in return, I will raise no objection-"