Rad Child (Fallout: New Vegas)

Rad Child is a perk

Effects
When affected by any sort of radiation sickness, receive increased health regeneration.

The health regeneration kicks in when the player gains radiation sickness and becomes more powerful depending on the severity:
 * Minor (200 rads): +2 health per second
 * Advanced (400 rads): +4 health per second
 * Critical (600 rads): +6 health per second
 * Deadly (800 rads): +8 health per second

Death will still occur when reaching 1000 rads. This perk does not heal limbs.