"The creative team considers how the personality of each character translates into facial expressions, body language, props, and home environment. The Mane Six -- Twilight Sparkle, Rainbow Dash, Fluttershy, Apple Jack, Rarity, and Pinkie Pie -- each have expressions and style characteristics that are unique to that character, as well as general expressions that they all share. According to the DHX Media team, 'There are certainly characters that would make different expressions, like you might do something with Pinkie Pie that you would never do with Applejack or Twilight or Rarity. So we don't have something that's specific for just one character, but we avoid certain expressions if it goes outside their personalities.'"
From My Little Pony: The Art of Equestria by Mary Jane Begin
