I don't know for certain. It could be based on some truth or could be the author's imagination. You'd have to research more or ask the author to know for sure.
Actually, 'The Night Of' is purely fictional. The creators came up with the story and its elements from their creativity, not drawing from real-life incidents.
Definitely not. Silent Night, Deadly Night is purely fictional. It was crafted by writers and filmmakers to bring a terrifying tale to the screen without being rooted in real events.