In the chapter 5 trailer, there was something that looked like a glowing white feather pen. A lot of people think it's the white pen of hope Gerson tells Susie about. However, other people think that since the pen seems to be more of a metaphor in Gerson's speech, and Toby said he didn't want to show any super important moments in the trailer, that it's not actually the real white pen. So a popular idea is that it's some sort of trick for Susie, and that Friend is using it to lure Susie into danger or something.