When you have entered the house and Sandra the babysitter attacks you, it is possible for her to kill you twice. Once when you are trying to get away from her in the kitchen and once when you are crawling away from her towards the glass door.
Once you grab the hammer from Clementine, you can either bash the baby sitter’s head in just twice to make her stay dead, or go to town on her face and repeatedly hit her, turning her face into goop. Either way will make her stay down for good and will always have the same outcome.
After you beat her with the hammer, Clementine will ask you if you killed her. For all of the dialogue choices, it will say that “Clementine will remember that” except for the option of saying nothing. If you choose that option, it will say that “Clementine seems afraid.” Although there are two different outcomes for the dialogue options, they don’t seem to have any affect through the episode.