“… Open up your eyes”
 
Eve’s condition is sort of a slight “ironical” reference to Tempest’s song in the movie. L.O.L.
 
Eve’s blindness is very likely the result of a deformation due to Tempest’s broken horn affecting the functioning of the genderswap spell used on her for the sake of Twi and Tempest having a biological baby. Although it could have never been intentional, Tempests deeply blames herself for it, believing it’s punishment for all the years she spent terrorizing and hurting other creatures along with the storm king. Eventide is one of the most precious things on earth to Tempest, if not the most, and Tempest is endlessly protective or her. She would do anything and everything for her baby.
 
 
I wish I had done a better job at this, or drawn a different scenario (this was actually supposed to be a pic with Twilight too, shortly after Eve was born and she had opened her eyes for the first time, but I felt lazy and wanted to post this quickly lol)