As is stated on Wikipedia, ghost #4 is called The Withered Lover ...
It is written as such:
The Withered Lover is Jean Kriticos, Arthur's wife. She was burned severely while saving her family from a devastating house fire, and died of her wounds in the hospital. Her ghost initially appears in a hospital gown, hooked up to an IV pole and showing severe burns on her face. However, after the destruction of the machine, her ghost is wearing her normal clothes and her burns have vanished. Unlike the other ghosts, she is not a vengeful spirit and tries to help her family.Unlike the other ghosts, she is not a vengeful spirit and tries to help her family.