Living Anatomy (Fallout Supplement)
From D&D Wiki
You have a better understanding of living creatures and their strengths and weaknesses.
Prerequisite: Level 5, 10 skill ranks in the Knowledge(Earth and Life Sciences) and Treat Injury skills.
Benefit: +2 bonus on Treat Injury and Knowledge (Earth and Life Sciences) skill checks. +4 Hit points healed when using Treat Injury.