Can multiple people hallucinate the same thing at the same time ?

[LazaB]

I know about mass hallucinations but that still doesn't explain how can 2-3-4 people see the same thing down to the details in one room , i think that cloud shape and miracle of the sun is easier to explain because not all witnesses saw the same thing , so it's easier to say that they were all wrong , but how the hell can multiple people see the same details on the person who is not even there ?
I am sorry if i am boring you with this but i always tell people how these stories are bullshit so it bothers me that i can't explain this

No, you are not boring anyone. I would only advice you not to believe everything people claim even in groups. Most of the world's population believed the earth was flat, and unfortunately there are still idiots today that still do. 

I understand , it just bothers me that we don't have a satisfactory explanation for those things ( other than the people are lying or hallucinating the same thing) , i found another one that scares the shit out of me
" When my grandmother died one of her sons, his wife and two children, a boy and a girl, moved into the house. My grandparents had lived in that house for over 40 years. To condense it down to the short of it, one day the daughter, who was 20 at the time, heard her name called, turned around in the kitchen to see her dead grandmother standing behind her. She obviously wigged out, dropped the glass she was holding which broke on the floor and ran outside and locked herself in her car. Nobody was home at the time. When my aunt and uncle arrived they couldn't coax her out of the car for a while. She explained what happened and my uncle said yea, I saw her too recently walking down the hallway.  As it turns out, they had all seen glimpses of her in the house but hadn't said anything to each other because it was "crazy." The thing that bothers me most about this is my uncle is a high school history teacher and football coach, my aunt works at the county clerks office, and the two children were more like young adults ages 18 and 20 at the time. None of the four of them are prone to flights or fancy, do drugs, or are known for lying. I have no way of understanding the stories they tell about that house. I simply can't explain it. The son, who was staying in what used to be my grandparents bedroom started sleeping on the couch because he would wake up and my grandmother would be in that room with him looking out the window.