This gave me an idea: I should find a pretense to gift my relatives with a picture of St. Michael the Archangel.  I'll have it blessed by a priest or monsignor first, of course.  I had suggested that the mother and father speak with a priest about their experiences, but the mother did not seem to be interested in doing so--perhaps she didn't think that priests could do anything about it.  I'll also try to get the kids to learn the Prayer to St. Michael.

Perhaps I should mention to the priest that it is intended for a Catholic family who think that their home may be haunted.

Does anyone know anything of the history of the house? It may be that previous owners or tenants conducted seances or other occultic acts therein, & thereby brought about its infestation. Or, perhaps someone committed ѕυιcιdє on the premises, or was a blasphemer. Holy Water & Exorcized Salt may help, although an exorcism of the house would of course be best. When I was a young fellow I lived in a rented house with my mother that had about it an an atmosphere of evil. We felt a sense of indescribable menace at times, as if we were being watched by something hostile. We were not yet converted at the time, but even so felt instinctively that the phenomena was of diabolical origin. I somehow knew that someone had died in the house & related my suspicions to mother, who later in the course of a passing conversation told the landlord what I had said. She said that he stood looking at her in disbelief for a few seconds & then asked how I could possibly know that; that indeed an old woman had died alone in the house years earlier. We were certainly glad to move when the opportunity presented itself.

I don't believe in ghosts, it goes against Scripture and Catechism. When a person dies they have their particular judgement and either go to heaven immediately or to purgatory to await the general judgement. They do not become ghosts. If something is happening in your home and things are being physically moved, you have a demon or demons around. Call an exorcist immediately. I will say I would even accept the existence of extra-dimensional aliens or even invisible earth creatures (do a youtube search for 'flying rods', they are quite interesting.)

But the human soul does not just wander around after death, it cannot.

I don't believe in ghosts, it goes against Scripture and Catechism. When a person dies they have their particular judgement and either go to heaven immediately or to purgatory to await the general judgement. They do not become ghosts. If something is happening in your home and things are being physically moved, you have a demon or demons around. Call an exorcist immediately. I will say I would even accept the existence of extra-dimensional aliens or even invisible earth creatures (do a youtube search for 'flying rods', they are quite interesting.)

But the human soul does not just wander around after death, it cannot.

I wouldn't waste your time worrying about aliens.