Princess Celestia and Twilight Sparkle's bond is tested by miscommunication and guilt.

Twilight is adopted; Celestia is unsurprised.

Nightmare Moon visits Twilight in the night, and things get biblical.

Twilight composes a letter about a terrible Hearth's Warming gift.

There's nothing worse for a pegasus than falling.

Summoned to the palace, Twilight takes up a burden that even she may not be able to handle.

Luna, Rarity, and Applejack meddle in Fluttershy's crush on Big Macintosh.

Celestia and Twilight Sparkle go through some issues because of the latter's new diet.

The truth about the creation of two prominent Twilestia stories is even stranger than you think.