In the "Investigate the beach" quest next to the druid cove with the harpies there is a glitch in which the tiefling child Mirkon can be brought back to life. I think if you have reached the part in the game where the tieflings leave the Druids grove and haven't saved Mirkon from the beach he dies. In my play-through I didn't discover this quest until after Mirkon was already dead. I killed the Harpies and had Astarion feed on the corpse of Mirkon which miraculously brought him back to life and made his way back to Mol's den which has been vacated already.
