Ken Walsh is the father of Jesse Walsh in A Nightmare on Elm Street 2: Freddy's Revenge, A Nightmare on Elm Street 2: Freddy's Revenge (novelization), A Nightmare on Elm Street 2: Freddy's Revenge (book adaptation by Bob Italia), and Jesse's Lost Journal.
Role in "Freddy's Revenge"
Ken Walsh is a typical nuclear family father whose role in the film is simply to cause frustration for his son Jesse. Early in the film, Ken is insistent upon Jesse unpacking his bedroom until finally having to force his son to do it. Afterwards, he begins to have antagonistic feelings towards Jesse. When one of Angela's birds explode, Ken accuses Jesse of using cherry bombs to cause it to happen. Later, when a naked Jesse is brought home by the police after Coach Schneider's murder, Ken shows that he cares about his son while also demanding to know what sort of drugs Jesse is taking and who is supplying them.
Somewhat mule headed, Ken refuses to acknowledge what he doesn't understand. Rather than fixing his air conditioner, he insists that it just needs a shot of freon. Ken, however, does not give it this simple shot of freon throughout the entire movie.
Ken purchased the house that Nancy Thompson grew up in for a discounted price, due to the death of Marge Thompson having occurred in the house. Ken kept this information from his wife, Cheryl Walsh. Upon discovering what her husband did, Cheryl becomes irritated at Ken's action.
Jesse's Lost Journal
In Jesse's Lost Journal, Ken Walsh is explicitly depicted as a pedophile and child molester. It is implied that he molested his daughter.