Family Curse (3.5e Flaw)
From D&D Wiki
Someone in the your family did something to inflict a death curse upon their entire family, example-The PC's grandfather was a powerful paladin who was cursed by an evil wizard as he struck him down.
Effect: The character suffers -1 on all skill checks.
Roleplaying Ideas: The character has fallen to evil as a result of experiencing firsthand the power evil can possess, the character has become a champion of good seeking to cleanse the world of evil to prevent others from ever having to suffer the same fate, the character may have become bitter at the gods for allowing such suffering upon the world, the character may hate all of the same class as the person who put the curse on their family whether good or evil, the chatracter may try to become the best at what they do to prove themselves above the curse, or the character may have become used to failure and as such is mildly depressed and has an I couldnt care less attitude.