Trivia: Black Phillip, the goat, was supposed to appear in a several other scenes. But the goat was so poorly behaved on-set, his role in the film was drastically stripped down. The goat often either refused to do what the trainers told it, or in some ugly cases, he would randomly attack cast and crew members. Co-star Ralph Ineson even had to perform the bulk of the film under heavy painkillers after the goat slammed into his ribs and injured him.
Trivia: Robert Eggers often had co-star Ralph Ineson direct child actor Harvey Scrimshaw during filming. Eggers has no children of his own, and wasn't sure how to communicate with the young actor. So Eggers would describe the scene, and Ineson, a father with two children, would then reinterpret his direction in a way Scrimshaw could understand. (Often by relating it to sports, since Scrimshaw is a huge soccer fan, and literally "coaching" him like a soccer coach).
Trivia: It's shown that there is mold growing on the family's corn. If you look close, the mold is a specific type called ergot. Ergot poisoning can cause severe symptoms including hallucinations, irrational behavior and death. Director Robert Eggers has said this was a purposeful choice, as he left clues for different possible interpretations of the film. If audiences want to believe the supernatural elements, they can. Alternately, they could chalk it up to ergot poisoning driving the family insane.