In "Vote For Brady", Greg tells off his campaign manager when he suggests running a smear campaign against Marcia. And when the manager announces he's going to do it anyway, Greg fires him on the spot.
In the episode "A Firstful of Reasons", Peter tries to reason with Buddy Hinton in order to make him stop bullying Cindy. When he fails and Buddy demands a fight, Peter gives him a punch that sends him sprawling into the dirt and knocks his tooth loose. The bully even admits later on that Peter's got a great left hook.
