I am not so sure, but following to get ideas. I made a star doll for my baby, and she had zero interest in it. Then I added more of a face to it (I know, I know... waldorf people avoid faces for a reason, but I am not dogmatic and it was still a sweet, simple face) and THEN she recognized it as a "creature" and smiled when I snuggled it up against her at bed time. It's still not really catching her attention much though, but she is younger than your DD.
I don't think she gets the idea of a "baby doll." Abstract ones like thew Waldorf star doll just get ignored. Then we have another plastic-face hand me down from when I was a kid that looks pretty realistic. When it's jumping around and goofing, she likes it, but when it is immobile, it scares her. I think she believes it's alive and when it goes limp, that it's hurt. So we put that one away until she is more mature.
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