Draconic Toughness( Races of the Dragon, p. 105)
Your draconic nature reinforces your body as you embrace your heritage.
Draconic Heritage (RDr) , sorcerer level 1st,
When you take this feat, you gain 2 hit points for each draconic feat you have, including this one. Whenever you take a new draconic feat, you gain 2 more hit points.