The 2019 Pet Sematary remake made a huge swap that was spoiled early in the film's marketing campaign and is the center of why so many didn't enjoy the new adaptation, but the choice to transfer Gage's fate to his older sister, Ellie, was a good decision.
Pet Sematary is one of Stephen King's darkest novels, and he almost didn't publish it because of the content. Even so, it remains one of his most iconic works. The story deals with a huge taboo in horror, the death of a child, and also explores the notion of grief on the whole, particularly how it is experienced by those who are left behind. The original story follows the Creed family to their new home in Ludlow, Maine, after making the decision to move away from Boston for a more rural lifestyle. After the unexpected death of Ellie's cat, Church, who is killed by a truck in the road in front of their house, Louis is introduced to the mystical aspects of an ancient Native burial ground beyond the Pet Sematary where local children bury their dead pets by their new neighbor, Jud Crandall.
After the resurrected Church exhibits irrational and violent behavior that is a far cry from his previously sweet demeanor, Louis learns why Jud says "sometimes dead is better". Yet when one of his children is killed, Louis decides to ignore all the warnings and take matters into his own hands.
Gage Creed Was Too Young To Be Effective
In the story, Gage Creed is only three years old. Fans of the book and 1989 film adaptation agree that, while tragic, Gage's death is the most sensible because he is innocent and the most vulnerable family member, so his death hits the hardest and is the most effective conduit for Louis' descent into madness from his subsequent grief. However, the young actor who portrayed Gage in the original film, Miko Hughes, didn't portray the resurrected Gage's murderous tendencies. Most of his darker actions were done by use of a doll. Since Gage is, in many ways, the primary antagonist of the novelization other than Church the cat, it's important to make this role solid for the screen. Aging Gage up wouldn't be as heartbreaking, and in a modern take, he could been portrayed using CGI or some other form of puppetry as the original film did, but it wouldn't have felt as organic as what a flesh and blood actor could do. Also, asking a very young child actor to take on something so insidious is never a good idea, and is out of the scope of their natural capabilities.
Pet Sematary Is About Grief and Death... Which Ellie Understood
Ellie Creed is still a child, but has a deeper understanding of life and death since she's older. While she isn't as much of the focus in the original story, the remake set her character up for its fate by having her mourn the loss of her cat, Church, and care for him after he returns. Her parents try to figure out how to explain Church's death to their daughter, unsure whether she'll be old enough to deal with the loss, but she seems to do so remarkably well.
In the original story, the aspect of the Wendigo is broached by Jud when he tells Louis about the Micmac burial grounds; he explains that those who return are inhabited by the spirit of the creature, and they don't come back the same. However, when Ellie returns, she is still human-like, showing a clear-headed awareness for her condition and even seeming to accept it in a way her parents can't. One of the most chilling scenes of the remake is when Louis tells his wife, Rachel, to hug Ellie after she is freshly risen from the grave. Ellie possesses the same darkness as her cat, with violent tendencies that allow her to wreak havoc in the film, and is portrayed by Jeté Laurence with haunting skill. Ellie seems to understand very clearly that she's dead and her father made the selfish decision to bring her back. It lends an existential dread to the film that, in some ways, makes it even more terrifying than a more traditional evil child would.