Frank Heffley

Frank Heffley is Greg's, Rodrick's, and Manny's father. He is the husband of Susan Heffley (Greg's mom).

Frank has a strong interest in American History, and this is implied in Rodrick Rules, as he builds up a Civil War Battlefield. So far, he is emotional to Greg. He is constantly bothered and troubled by such small matters, and always wants his Sons to look good in his boss, a very small matter that Frank constantly gets worked up about. He hates Rowley, video games, heavy metal music as well as teenage delinquents. He is a hard worker, and has a poor relationship with all of his sons, since the three cannot relate to each other at all. He is also shown to be a junk-food addict as well, possibly hinting that Frank may have a high cholestrol.

In the third book, Diary of a Wimpy Kid: The Last Straw, Frank gets fed up with Greg's behavior and threatens to send his son to Spag Union Military Academy to toughen him up, because the academy turned Lenwood Heath, a prankster, into a polite young man. Greg tries to circumvent this by proving to his dad that he does not deserve this treatment by "doing his best" in soccer and joining the Boy Scouts, among other things, but ultimately fails. It is not until Seth Snella's half-birthday party that Frank realizes that his son's wimpiness is a good thing, because it saved himself from looking foolish in front of the entire town.

In Dog Days, Frank has a rather minor role in the story until Father's Day, where Grandpa admits that he lied to him about his dog, Nutty, running off to a "butterfly farm", and instead admitted that he accidentally killed his dog. Frank, in response, becomes furious, and decides to buy another dog to make up for the lost one. This dog was named "Sweetheart" much to the three siblings' dismay, or Sweetie for short. Frank becomes obsessed with this dog, even though Sweetie is two times as lazy and repulsive as Greg.