This discussion may contain spoilers!
Does everyone remember first meeting Sarah and choosing whether to be her friend in Episode 1? If you chose to be her friend, she sealed it with a pinky promise. Moving on now to the present, Sarah has ran away at the end of Episode 3, but I believe that this isn't the last we've seen of her. If worst comes to worst and she becomes determinant in Episode 4, would you choose to help/save her? Despite how much people here seem to be annoyed by her, I think that she's a good person who needs a friend now more than anything. I would definitely help/save her or at least try to. Oh and on an unrelated side note, I would just like to mention how great Sarah's voice actor is. Louisa Mackintosh has got a really sweet voice and hones the character well!
Based on the trailer for Episode 4, it looks like Sarah will most likely become determinant. It's so sad. I hope most players will make the right decision and try to help her, if it's possible.
Rather than build character development and make Sarah into a stronger person, Telltale has decided to kill her off despite all attempts offered to save her. It's a real shame that inspiration was lost for such a good character. However, there's no doubt that every friend-option scene Clementine had with Sarah till EP4 was just like how a true friend would react or care for another. Well done, Telltale.
Sarah had a special personality of naivety and kindness that most people don't have or appreciate. I hope maybe someday Telltale will change how they handle some of their characters, though.
Good bye, Sarah...