"The Exorcist", "The Omen" and "Carrie" are all highly regarded 70s demon child movies thought to be the progeny of "Rosemary's Baby", and there are many similar themes between the three movies, as well as similar characters, and many striking differences. The Chris from "The Exorcist" is the hero; Chris (MacNeil) who is the mother of the demon child in "The Exorcist". The Chris in "Carrie" though, Chris Hargenson, is the villain of that story, the bully who spills the pigs' blood on "Carrie". Similarly William from "The Exorcist", Lt. William Kinderman, is one of the heroes of that story, the detective who is trying to solve the Burke Rankings murder, whereas the William from "Carrie", Billy Nolan, is one of the villains who kills the pigs that they use to spill blood on "Carrie" with. Karl from "The Exorcist", Chris' cook and Butler, is a nebulous character who could be either good or bad; whereas Carl from "The Omen", Carl Bugenhagen, is one of the heroes of that story, he is the exorcist who gives Robert Thorne the knives to kill Damien. Damien on the other hand is the hero of "The Exorcist"; Damien Karras is the priest who stops the demon at the end of "The Exorcist". Whereas Damien in "The Omen", Damien Thorne the anti-Christ, is the villain of the "Omen" series who is trying to bring on Armageddon. Tom in "The Exorcist" is a priest who is trying to help the heroes; and Tom in "Carrie", Tommy Ross, is the kind boy who befriends Carrie at the ending and tries to make her feel loved. The nanny in "The Exorcist", Sharon Spencer, is a good character who is trying to help Chris and save Regan. The nanny in "The Omen" is an evil character, Mrs. Baylock, who is also trying to save the demon child of that story, but will do it by any means possible, even if it means killing the rest of the Thorne family. The father in "The Omen" is good; Robert Thorne is the hero who is trying to stop the anti-Christ. The father in "Carrie" is nebulous, Ralph White has abandoned Margaret and Carrie before the story starts; not enough information is provided to enable the audience to know him well enough to know if he caused all the problems in the story or not, although Margaret accuses him of raping her at the ending, and Carrie says he ran out on them; and he has not kept up with Carrie either, he abandoned her when she could have used his help in dealing with her mom; so all of this does make him seem bad and negative. And the father in "The Exorcist" is definitely bad; he runs out on Chris and Regan, does not even check in on his daughter on her birthday, or even when she is battling Pazuzu, and obviously does not care about her, and it's hinted that his abandoning the family is what allows the demon to get control of Regan in the first place. The mothers in "The Exorcist" and "The Omen", Chris and Catherine, are both good, although Catherine might be more of a victim, whereas Chris might be stronger; she stands up to evil and saves her daughter and herself in the ending. And Margaret, the mother in "Carrie", is very evil and crazy, and her abusiveness towards Carrie, and her insistence on keeping her shuttered away from the rest of society is what sets up the bullying dynamic with the other kids in the story and the tragedy at the prom as well. The demon child attacks all three mothers in the stories; in "Carrie" she kills her, in "The Omen" he knocks her off a step stool with his big wheel tricycle, and in "The Exorcist" Regan throws Chris against a wall and telekinetically shoves a chest of drawers in her direction. There is an exorcist in all three stories and they are also different. In "The Exorcist", the exorcist of that story is one of the heroes, Lancaster Merrin, is trying to save Regan from Pazuzu. The exorcist in "The Omen", Carl Bugenhagen, is also heroic, but he is trying to kill the demon child in "The Omen", not save him. There is also an exorcist in "Carrie", Margaret White, who does an exorcism ceremony on her daughter after she goes to the prom; although unlike the other two exorcists who are good, Margaret is quite crazy and winds up trying to kill her daughter at the end of "Carrie". The three demon children are also strikingly different. Regan in "The Exorcist", is a good girl with an evil demon trapped inside her, and for most of that story, because she is possessed, she is actively evil and trying to kill, corrupt and destroy the people around her. Damien, however, is the anti-Christ, but he does seem to be fully aware of his evil and his powers; until the final chapter of this series. He seems to be manipulated by evil forces around him for most of "The Omen". Even in the infamous tricycle scene, it seems like he's being manipulated by his father, the Devil, and isn't completely aware of what he's doing in that scene. Carrie on the other hand, is a sympathetic demon child; for most of the story she is a very sweet, put upon victim character, and when she finally does use her powers, it's only because evil people around her have pushed her into it; and they more or less deserve her punishment of them, unlike the demon children in "The Omen" and "The Exorcist".