There is a doll exist called Annabel, it is real and people believe that it possesd by a demon
It is kept Warrens' Occult Museum present in Monroe town in USA.
The Annabel story in which the doll was with nursing students and they seen unusual things from doll, for example the doll itself change position in room, it write notes on paper like help me, it tried to attack a boy, all these things are revealed by ed and Loren who are famous paranormal investigators.
But all these things are just stories, there is no interview or any video of a nursing students who claimed that Annabel doll is haunting, these stories are made by ed and Loren.
Second thing about Annabel people believe that you can't insult the doll, if someone try to insult it Annabel will take revenge, story of a cruch father and a boy was there regarding this incident , but again these stories don't have any proof it is propagated by ed and Loren.
Claims which are made on annabelle to show that doll is possessed by a demon are mostly by ed and Loren but none of their claims have proper proof.
So Annabel is a normal doll there is nothing like it is possessed by demon. You can remove it from museum and you can pass comment on it like me, I always find that doll very funny, of course in the movie that doll have a scary apperance but in reality it looks very funny and normal.
Ed and Loren probably used this doll stories to make money, they sold the stories to novel writers and Warner brothers( popular hollywood movies production company ). Because of which we have the Conjuring universe