Nonsense that goes nowhere

Rating: 3/10 (10 May 2020)

Several random scary things happen, but with no reason or logic. The movie sets the atmosphere well, and has some interesting thematic possibilities, but the latter are never realized. For example, the use of miniatures isn't developed as it could have been. And the witch theme could have been developed to some moral purpose.
Is this movie a psy-op to defuse concern about actual occult practices ?
What exactly is hereditary ? Grandma is a witch, but that power is not passed down ; instead, she curses her own grand-daughter, I guess, though it's not clear how she accomplished that, and it turns out to be a mistake.
Why does burning the notebook cause the mother to burn ? What is so important about it ? The demon doesn't seem to need it or care about it. Then, later, why does the father burn instead ?
How was the son possessed ? The seance invites the demon into the house, but it must take some kind of complicated ritual to cause a possession.
The mother is normal, and tries to prevent the possession ; so why at the end does she suddenly become a witch herself ?
And anyway, Why are all the females decapitated ?