Once Bitten, Part 1
During her escape from the mines, Emily may end up being bitten by the Wendigo. However, this isn't as serious as you might think. You'll learn more shortly.
Point Blank, Part 2
Chris will have to fight his way back to the cabin after the Wendigo kills the Flamethrower Man. Shoot the thing at every chance you get, and when you get back to the house, Ashley will be there to open the door for you.
Once Bitten, Part 2
If Emily got bitten by the Wendigo, then at some point in the safe room everyone will find out and Mike will point a gun at her - make sure you don't pull the trigger, so you spare her life and the truth about her bite can be discovered.