Bless the Child

A story about a (virgin?) mother and her adopted child - who just happens to be the messiah.

The adult main character gets a brief visit from her drug-addicted sister, who drops off her new baby. Fast forward a number of years, and the child is in a Catholic school for disabled children. She is believed to suffer from autism, but it is indicated that she has started to develop supernatural powers - making plates levitate, and more importantly resurrecting a dead bird. Things are going well.

Then one day, the sister comes back to claim her child. Or rather, her new husband has come to claim his new wife's child...

Tropes used in Bless the Child include:

Affably Evil: The bad guy is really nice and polite about his murderous plans - even when he has a gun against his head.
Black and White Morality: As black and white as it gets, with the child being the messiah and the antagonists literally being agents of the Devil.
Captain Ersatz: The girl is not Jesus, but she is Christ.
Church of Happyology: The New Dawn. Pretends to be a Self-help organization, but is really a religion? Check. At the same time, it pretends to be a honest religion but is really an evil scam? Check. Leader-worship? Check. The cult secretly hates Christianity? Check. The cult's propaganda and centers looks exactly like Scientology propaganda and centers? Check. Harasses defectors? Check. Has an army of lawyers? Check. People are actually possessed by countless thetans/demons? Check. The cult uses e-meters to count how many thetans are possessing your body? Actually not check, the line has to be drawn somewhere.
Clap Your Hands If You Believe: Beware of old nuns, they can pray. And in this setting, prayer is a very powerful weapon.
Cult
Disability Superpower: Cody's telekinesis and ability to resurrect the dead is tied directly to her autism.
Eye Scream: A guy gets a knitting needle in the eye.
Horror Doesn't Settle for Simple Tuesday: Easter is prominent.
Infant Immortality: The girl, but not any of the other kids the cult targets.
Masquerade: Angels and demons are everywhere, fighting their war without anyone noticing.
Mind Over Manners: Cody is extremely polite, using her good manners not only to keep her other powers in check but also as a superpower in itself. She actually uses it to defeat the Antichrist.
Religion of Evil: The local Church of Happyology is actually a front for an ancient cult of "luciferian" devil-worshipers.
Religious Horror
Villain with Good Publicity: The bad guy keeps his devil-worshiping and destructive ways secret, successfully pretending to be a great humanitarian. And no, not in that way.