A death in the family Achievement
A death in the family160
This could be missable if you don't do it right.
This will happen at the end of the game. You will have two choices to make: either reject Adam or not.
You can pair this with "Embrace Adam": as soon as the credits roll, the achievement should unlock. When this happens press your guide button (the one in the middle of the controller) and quit the game to the dashboard. Simply load the game back up and continue and you should start at the end again. Now pick the other choice to unlock "Embrace Adam."