Leo Anthony Gallagher Jr. (July 24, 1946 – November 11, 2022) was an American comedian. His prop and observational routine included the signature act of smashing a watermelon on stage with a wooden sledgehammer.
In "Frannie 911", when Roger brings a sledgehammer and a watermelon into the study, Francine thinks it might be "Gallagher Day".
Roger, Hayley, and Jeff come into possession of Gallagher's mallet in "Stan Fixes a Shingle" after it falls off his tour bus in Langley Falls, and set out to return it to him. However, Hayley accidentally breaks it trying to smash a watermelon from Jeff's van. As the trio arrive to Gallagher's next show in Long Island, Jeff fatally strikes Gallagher onstage with his van, which makes Jeff's van a comedy icon and "the new Gallagher" in the process.