Season 3: Episode 42: Peter Griffin: Husband, Father...Brother?

When Chris begins to embrace African-American culture, Peter takes him to an Irish heritage museum to teach him about his own culture. In a genealogy book, Chris discovers that he has an African-American ancestor. Meanwhile, when the Peterschmidts come to visit, they reveal a secret and bribe Peter to keep it quiet. But after Peter accepts the bribe, he makes a harsh realization.