When Stan defecates in Buckle and Sharri's pool while doing a cannonball in "An Incident at Owl Creek", he tries to hide under the kitchen sink, disturbing Frank. The family talks Stan into coming out, but, everywhere he turns, he sees people laughing at him. Unable to take it anymore, Stan blows up his house to fake the family's death, setting Frank on fire and running him over as they leave. It is later learned that the entire episode after the scene on the diving board was a fantasy of Stan's meaning Frank was not run over and killed. This also possibly means that Frank may not be real, just a figure in Stan's dream.