Is it normal my girlfriend talks to her stuffed animal???

So I bought that little stuffed animal for my girlfriend. It's a little white, fat bunny. She called it "Marshmallow". The weird thing is, my gf started to talk to it. At first it was funny, but now she gets angry when i say that its not real, and i even have to talk to it like to a real person. She says that Marshmallow wants to be a pornstar, and that it has a very deep voice. IIN???