Sandra (Video Game)

Sandra was the babysitter of Clementine. Clementine mentions her screaming a few days before Lee Everett arrived at the house implying she was attacked by a zombie and reanimated.

Rural Georgia
Not very much is known about Sandra's life. She was likely a paid babysitter for Clementine. She was asked by Clementine's parents, Diana and Ed Marsh, to look after their daughter while the two were on vacation in Savannah. She was supposed to call the parents back about the situation with Clementine but she was never able to do so.

Episode 1: A New Day
It is implied that Sandra was attacked by a zombie two days before Lee Everett arrived at Clementine's house. When Lee enters the house and looks around, he spots a pool of blood likely from Sandra and then hears Clementine on a walkie-talkie. When Lee slips in the pool of blood, Sandra crawls for him. Clementine arrives at the sliding glass door and hands Lee a hammer which he uses to kill her.

Killed By
Clementine says she heard Sandra screaming a few days before Lee Everett got to her house and then reanimated soon after. It can be implied that she was attacked by walkers. Lee Everett slips in her pool of blood and she crawls after him. Clementine walks to the sliding glass door, opens it and gives Lee Everett a hammer. He then proceeds to beat her on the head with it repeatedly and kills her.
 * Walkers (Alive)
 * Lee Everett (Zombified)

Trivia

 * Clementine's parents mention her name during a phone recording.