Here's part of Wikipedia's plot summary for Paranormal Activity 3:
In 2005, Katie delivers a box of old videotapes to her pregnant [younger] sister Kristi...which holds footage of young Katie and Kristi with their mother, Julie, and her boyfriend Dennis.
In 1988, in their house in Santa Rosa, California, Kristi begins interacting with an imaginary friend named Toby. Dennis notices that since Kristi's friend appeared, strange things have been happening around the house. Dennis and Julie try to make a sex tape, but are interrupted by an earthquake. The camera shows dust fall from the ceiling and land onto an invisible figure in the room. While reviewing the footage, Dennis notices the strange incident. His friend Randy suggests that Dennis place cameras throughout the house to capture any other incidents. That night in the girls' bedroom, Kristi wakes up and talks to someone off-camera. When Dennis questions her the following day, Kristi tells him it was Toby.
The plot summary goes on for several paragraphs but what it doesn't make explicit is that Toby, who is described in the film by Kristi as being "old like Grandma", wanted to have sex with Kristi to produce a male heir. The Villain's Wikia sums it up better:
Toby was growing impatient and wanted to mate with Kristi to father her child in hopes of producing the male heir he had been promised. Kristi [initially] refused to give in to his demands and told Toby to stop talking to her. In a rage, Toby gave Kristi a high fever and brutally attacked Katie and Dennis' assistant Randy the following day. Later that night the furious demon trashed the girls' room and dragged Katie into his crawlspace, holding her hostage until Kristi agreed to do as he asked. Toby told her to go to Lois' [the grandmother's] house to prepare for a binding ritual.
The film ends as Lois lures Kristi and Katie upstairs saying, "Let's get ready," before Kristi excitedly request that Toby join them.
Mad Max: Fury Road (2015) is approximately two hours of almost non-stop carnage as Immortan Joe violently attempts to recover his five, much younger, wives whom escaped with warrior Imperator Furiosa (Charlize Theron) with the help of Max Rockatansky (Tom Hardy).
Lastly, the novel and the film The Lovely Bones is about how 14-year-old Susie Salmon was raped and murdered by George Harvey her 36-year-old neighbor in Norristown, Pennsylvania. Interestingly, the film doesn't make it explicitly clear that Salmon was raped.
In all of these films it appears that the underlying theme of hebephilia\ephebophilia and in the case of Paranormal Activity 3, pedophilia, is lost in the engaging horror, action and\or storytelling.