My 6-year-old had a dream shortly after Christmas that her favorite baby doll came to life. She thought it was Santa magic. To sort of play along with her, I posed the doll a few times - once reading a book and the next time, looking out the window. Our daughter took this to be proof that the doll was alive. She really took it to heart and said she could really now be a big sister. It has only been a week or so, but she insisted on trying to feed the doll, take her everywhere and continue to watch for signs that she was alive. My husband felt our daughter was starting to obsess on this and worried that it might be harmful. Finally tonight, after she asked if I was starting to doubt the doll was real, I told her the Mommy had posed the doll with the book and looking out the window. She was devastated. I would greatly appreciate any perspective.
Daughter thinks her doll is real
At this point, I think I'd just sympathize with her... it would be fun to be a big sister, and it would be awesome if her doll came to life. Let her tell you stories about what the doll would do if it were really alive. If she's upset specifically that you posed the doll, then explain to her why you did it... she was having fun and you wanted to make her happy. Maybe talk a bit about pretending? She might just want you to pretend with her that the doll is real. I bet it was really fun for her to have you playing along.
My almost 6 year old DD's friend got a letter from Santa saying how good she was, and DD said "I must not have been very good since I didn't get a letter." I basically told her that Santa wasn't real, but she didn't want to believe me. After that, everything that was in a different spot than she remembered it "must have been put there by Santa." I felt like she kind of knew Santa wasn't real, but she really wanted to believe, so it got exaggerated. I wonder if that's what's going on with your DD? Anyway, I agree that playing pretend with her (with everyone understanding that we're pretending) might help.
I agree with pp. You can understand why she is upset and apologize for your part in that. Some kids are more sensitive than others regarding this sort of pretend v real stuff. Now that you know your daughter may be one that is more sensitive you can be extra cautious in the future about this type of thing. I don't think it was to the point where it was unhealthy...she is on the border of the age where things being real v imagined becomes more clear for children.