OK what's happening is as she dries out, the places that would typically be filled with moister are collapsing in on themselves, embalming is supossed to prevent this long enough to get the corpse in the ground, but places like the scalp, finger tips, lips, and yes eye lids are more difficult to get the fluid into. Which is why you here about a corpse's hair and nails growing post mortem, and why if you have an incompetent mortician stuff like this happens. The mortician is supposed to either sew or glue the the eyes and lips shut to prevent this phenomena and another similar one that results in the lips parting into what can look like a smile, a grimace, or a snarl. Sorry for long comment.
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