Princess Celestia, when not facing down end of the world catastrophes, has a very basic routine she's come to tolerate. From sunrise to sunset, the same schedule over and over. Listening, petitioning, more listening and then finally announcing her verdict.
When she's finally done with the affairs of the court and tending to the populace, she decides to go take a nap. To a special place that no pony can find her, a place that no pony would suspect a princess to safely secretly slumber . For where she's heading is worth more than a dragon lord's horde and it makes her happier than a day spent at a Summer Sun Celebration. It's a magical place that Celestia doesn't feel the eyes of everypony watching her. Magical Daycare.