Did your parents let you see this?
Mine sure didn't until I was old enough. It's traditionally rated 15 in my country, but now 7+ on Amazon Prime and 12 on the other streaming service. When I was little, my mum told me it was one of the scariest movies she had ever seen and compared it to The Exorcist. She said she had nightmares from the opening sequence.
Since it's PG in the U.S., then technically any child would be allowed to see it.