As the next chapter reveals, Gretchen’s feelings of guilt surrounding Ellie’s death are at least partly misplaced. It’s interesting that even after opening up to Falk, Gretchen refuses to admit that Luke is Lachie’s father. While it’s possible that Gretchen is telling the truth and that the photo of Luke with Lachie is just a coincidence, it’s also possible that Gretchen has determined that some secrets are too significant to ever reveal.