Princess Celestia, called Queen Celestia in one comic and early development, is an Alicorn pony, the co-ruler of Equestria alongside her younger sister Princess Luna (before their retirement in season 9), and the adoptive aunt of Princess Cadance. In addition to her responsibility of raising the sun, she is also a teacher to Twilight Sparkle and Sunset Shimmer at different times, often addressing Twilight as "my faithful student" while mentoring her. She has a pet phoenix named Philomena.