There is no conclusive evidence to prove that the Hannah Grace exorcism is a real story. Many so - called exorcism stories often turn out to be a mix of superstition, psychological factors, and sometimes even hoaxes. Without proper verification from reliable sources, it's hard to take it as a real event.
The origins might be in some form of urban legend or a fictional account that got passed around. It could have started from someone's made - up story which then spread through word - of - mouth or the internet.
I'm not sure about the specific real story of the exorcism of Hannah Stevenson. There are many so - called exorcism stories that are often a mix of superstition, legend, and sometimes fabricated elements. It could be a local or relatively unknown account that hasn't been widely documented in mainstream historical or factual records.
I'm not entirely sure which specific 'Hannah Grace' you are referring to. There could be many people named Hannah Grace. It could be about a particular individual's life journey, her achievements, or perhaps a story that has been made public about a Hannah Grace in a specific community or event.
The evidence that 'Haunting of Hannah Grace' is a real story might be somewhat scarce. It could be that the general concept of a morgue being a place of the unknown and the idea of something sinister attached to a body there is what they considered as real - life inspiration. There might have been accounts of morgue workers feeling uneasy or experiencing strange phenomena, which the movie took and dramatized. But it's hard to say for sure as the movie industry often blurs the line between fact and fiction for the sake of creating an engaging horror narrative.