This can be done split screen with 2 controllers.
Load up Mission 2 - Battle For Sulaco in campaign co-op.
A couple of minutes in, get to the part almost immediately after you open the huge door with the power-loader.
You will need to head right at the bottom of the first room with the eggs. Send player 2 just inside the corridor - when he gets to the end a face-hugger will jump out at him. Using a shotgun, just shoot him in the face, killing the face-hugger. Don't worry, player 2 will be immune to a shotgun in the face.
You need to be quick or else player 2 will die. In which case reload the checkpoint and try again...easy :)