The most obvious inspiration for the story, of course, is The Boy Who Came Back From Heaven, which is a nonfiction account by Kevin Malarkey and his son Alex (that’s really their last names . . . you can’t make this stuff up) where they claim that Alex saw Heaven while he was a in a coma. The boy later recanted, saying his dad had planted the whole story in his mind, and it was a huge mess, but for a while it was quite a cultural phenomenon. There was even a major studio picture, starring Greg Kinnear.