Daughter, age 3, suddenly seeing a "ghost" almost every night. Please HELP

Hello everyone.​Before we start this discussion, I am 100% atheist. I simply do not believe in spirits. However, I realize I need to be sensitive towards this subject in regards to my daughter's psyche and how I can help her understand that this is an imaginary friend.​Here are the details. We are divorced, my ex wife lives on the other side of town. I have my daughter every other weekendThur-Mon, my ex has her the rest of the time. My ex sent me a text explaining the full extent of the situation last week, as this just started last week.​My ex has lived in the same place for almost a year, my daughter, for the last week, has been randomly getting up in the middle of the night (1-3AM) and is being caught "playing" with "Granny". By playing, this means she is sitting in her room with ONLY the closet light on, talking to "Granny"​"Granny" is apparently an old woman who my daughter says never speaks to her, is nice, lives in the "turquoise edition" (we assume she means housing edition), and her face is covered in ketchup. We don't know what housing edition she refers to, but she says that "Granny" lives in her moms bathroom and comes out to play in her her closet with her at night.​Here's whats freaky, my daughter never knew the word turquoise or edition before last week, and to use them PERFECTLY in a sentence that had proper context was... unsettling.​I am convinced this is the manifestation of something she has seen in a show mixed with maybe partial, actual memories or something of the like. She watches Hilda, Goosebumps, Scooby-Doo, etc, so she is a very brave child and has also been exposed to very mild, child-friendly horror/suspense shows.​I have very calmly asked my daughter to explain "Granny" to me, but I don't want to keep bringing it up so that she always thinks about it and this never goes away.​How do I prod for details?​What questions should I ask and how should I steer the conversation in a way that I need it to go to fully understand what's going on?​What ways can I help her understand "Granny" isn't real without it upsetting her or de-railing her psyche / ability to differentiate real from make-believe?​Thank you everyone.​Sincerely-One freaked out atheist.​ via /r/Parenting https://ift.tt/2qYsq1n