— Mad-Eye Moody
Kill the spare.
"Bone of the father, unknowingly given, you will renew your son! Flesh of the servant, willingly sacrificed, you will revive your master. Blood of the enemy, forcibly taken, you will resurrect your foe… [t]he Dark Lord shall rise again!"
- Peter Pettigrew enacting the resurrection potion, Harry Potter and the Goblet of Fire