When a relative mentioned seeing her daughter three times in her home recently, I figured she was overwrought and upset, and just imagining things. You see, the daughter died a few months ago.

But instead of passing judgment on the mother by saying something like, “Oh, your eyes are surely deceiving you,” the situation prompted me to decide whether I really believe in ghosts or not.

Catholics believe in the invisible world, of course, as we proclaim in our creed with the mention of “all things seen and unseen.” That word “unseen” brings to mind angels and demons, and Catholics do believe in both. We also believe angels and demons at times can appear to earthly people, since we have evidence of that from Scripture.

But what about garden-variety ghosts, as in, “I saw Uncle Henry standing in the living room last night, even though he died 20 years ago?”

Catholic apologist Paul Thigpen helps answer this intriguing question in an online article called “What About Ghosts?” He explains that the saints in heaven, along with the souls in hell and purgatory, are disembodied spirits. Since ghosts are generally understood as spirits without bodies, then our Catholic faith certainly includes a belief in their existence.

It seems that when St. John was a seminarian, he and a friend made an unusual pact: Whoever died first would contact the other one in some fashion. The friend died April 2, 1839, and on the night after the funeral, a very strange thing happened. John was gathered with 20 other theology students in the same room, when they suddenly heard a very loud roar. What came next is definitely fodder for a good scary movie. It seems the door opened of its own accord, a dim light appeared and a voice called out, “Bosco, Bosco, Bosco, I am saved.” Not surprisingly, the theology students discussed this event for a long time to come.

“Saved,” according to Catholic theology, means the friend might be either in heaven or purgatory, since these are the two possibilities for those dying in a state of grace. Assuming the friend was visiting from purgatory, I wondered what might spur someone from that region to visit earth.

A little research gave me a possible answer. You see, there is a place called The Little Purgatory Museum in Rome. Although I’ve not visited it myself, there is a website where you can see photos of fingerprints burned into a prayer book and a charred hand print on a table. The folks who found the prints believed they had been left by deceased family members returning from purgatory to seek prayers and Masses.

Keep in mind that none of these phenomena has been officially approved by the Catholic Church—and you can make up your own mind about their veracity. In fact, Catholics are not obliged to believe in ghostly visits, nor are we forbidden such a belief.

Still, there are certain practices surrounding the ghostly realm that the Catechism of the Catholic Church definitely forbids. These include trying to contact the dead by getting involved in séances or Ouija boards. As Thigpen reminds us, such practices may indeed conjure up a spirit, but it could very well be a demon camouflaging itself as the dearly departed.

I don’t know about you, but I would hate to be a soul from purgatory desperately trying to get folks’ attention. As for my relative’s daughter, I plan to pray for her, now more than ever—and have Masses offered for her.

When it comes to prayers, we can never have enough. And when it comes to ghosts, I’d say it’s wise to err on the side of caution.