Specifically in the "A Woman's Lot" DLC the main character's dog, Tinker, is killed by a man with an axe in the last scene of the DLC and cannot be avoided. The death happens off-screen but you do see Tinker's deceased body (with no gore other than blood).
The protagonist becomes unconscious a few times in the beginning of the game. Non-player characters can also be strangled unconscious in their sleep at the players discretion.