Alas you have not found Caroline’s Treat, merely her favorite bird.
Owls have long been associated with Halloween, probably because of their nocturnal habits.
They are the only animal that can comfortably live with ghosts. If you find one nesting in an abandoned house assume it is haunted.
They are harbingers of death. Seeing/finding one nearby is an omen that someone will die.
They are associated with witches. Romans believed witches could turn themselves into owls. Other cultures viewed them as either messengers or creatures that warned of the approach of witches.
The hooting of an owl can harm a child-cause illness or an unhappy life.