Is It a Demon or a Human Ghost?

Poltergeist means noisy ghost or noisy spirit, not noisy demon. If it is a human spirit, it wouldn't seem to be acting like one of the saints during a heavenly apparition. They don't typically throw objects around. Sometimes people on earth need a bit of tough love and i can't rule out theible that a heavenly spirit might need to put the fear of god into people. And we do see angels doing that in the bible. But those aren't the only possibilities. As we discussed in episode six souls in purgatory and the damned can appear to the living.