*Heather Hills (known as Lori Matthews in the online book) is the older sister of Holly Hills and a teenage girl in Rodrick Heffley's grade. She is a notable character in the Diary of a Wimpy Kid series, appearing in Rodrick Rules and played a prominent role in Dog Days and served as the main antagonist in the Dog Days (2012 film).

Despite the country club requiring employees to be 18 and up, she somehow has a job there. It is likely she lied about her age or circumvented the rules. Though given that Heather is not really that smart, it's more likely the former (that she lied about her age). Another possibility could be she was in a volunteer position, as she mentioned that the only reason she was working there was to get credit for her college application.

In the movie, Heather drives a convertible and has her own cell phone.

In the film, as the main antagonist, her personality is shown to be that of the ultimate stereotypical valley girl. She is extremely ignorant, rude, spoiled, narcissistic, selfish, ill-mannered, self-absorbed, lazy, entitled, mean-spirited, cold-hearted, dense, obnoxious, bossy, cranky, grumpy, scary, loud, brash, as well as plain oblivious. Although Holly and Greg both describe her as the female-equivalent of Rodrick, she is shown to be far more ill-mannered, obnoxious, and mean-spirited than him, seeing everyone else as beneath her and caring about absolutely nobody but herself, not even her own family, and shows no remorse or regret for her actions. While Rodrick has a few redeeming qualities, Heather has none. In addition, her actions tend to be extremely reckless, as she once threatened to leave Holly behind at the club, acted rude to a girl when she asked for directions to the snack bar (even the girl called her out for her behavior by stating there's no need to be rude), refused to help Rodrick when he was “drowning”, and tried assaulting Rodrick when he accidentally knocked over her sculpture of her, destroying her cake in the process. and splattering it all over and Madison. Not helping is that Heather is a keep Houdini who doesn't get in trouble for her actions.*