As this is a Headscratchers page, spoilers will be left unmarked.
Okay, so everything that happens in the movie is because of the demon (presumably) summoned by the Brotherhood of the Ram. Then why do we keep seeing Annabelle's ghost around? Is the demon using her to help attack his victims, appearing as her to mess with people, or what?
Annabelle is the vessel the demon resides in. The human Annabelle transferred it from herself to the doll, once she realized she would be killed before her mission was complete.
There is no ghost of Annabelle. The demon is simply taking her form.
The prequel reveals that there was no "Annabelle Higgins" in the first place, her real name was Janice and she had been possessed by and under the full control of the Annabelle demon since she was a child, years before she was adopted by the Higgins.
