How do the canon alternative universes relate to Equestria Prime (if that's what we're calling it?) Got any theory about either verse? Post 'em here!

3418931 Sunset Shimmer was an orphan with poor magical abilities who was taken in by Celestia as her apprentice and daughter. She became big headed due to her newfound lifestyle and newfound magical proficiency due to Celestia's tutelage that it led to her going through the mirror to the human world. Once she was there, she was back where she started; alone and without magic.