To help her understand the ways of the Earth Ponies better, Luna nominates Applejack to take her in for a year and teach her the ways of a modern, earth pony farmer.
Twenty years before the Elements of harmony, before Nightmare Moon's Return, Celestia started a whole new slew of problems and headaches for herself and the ones around her. Thankfully Cadence doesn't mind foalsitting.
Changelings have been depicted as cruel, heartless, love stealing monsters. Multiple ponies across Equestria would love to watch the race burned from the earth. But nopony ever realizes that changelings too wear masks. And behind them, is tears.