Random idea:
A less horrific variation of Junji Ito's "Hell o' Dollies" story where a strange illness is causing young girls to gradually turn into doll-like effigies of themselves.
The illness works similarly like in Ito's story, where the girls begin to have issues moving on their own volition but keep their ability to speak for much longer.
However, instead of contorting into horrific...*things* like at the end of the comic, the victims start shrinking in size (losing their ability to freely move as they become progressively smaller).
By the time that victims have reached the size of an actual doll, they'll stop moving entirely (but will still be able to speak); unfortunately, by this same point, the subject's responsive and sense of self will eventually fade away too.
In the final stages of the illness, the now-inanimate dolls will gradually shrink down even further to a very small figurine (about the size of a figurine in a music box).
After that, the person is completely lost, and some families will hold on to the figurines for sentimental value while others will discard (or even destroy) them since they can potentially pass on the illness to other young girls.
Efforts are being made to vaccinate girls against the illness, but the best that can currently be done is halt the process during earlier stages (still ambulatory and responsive, but sometimes having already shrunken in size).