] I've just realised that there's something I don't know.

] Does anyone know when Cassandra drew/painted the picture of Jane?

It's not known for certain. But most have it dated to
c.1810. So you will have to look for other reasons for the
shadows under her eyes. We can only guess. What happened during that time? Was it just because she worked hard,in bad light,preparing for the publication of S&S? Had too little sleep? Or because the portrait was drawn during the bleak winter time? She used to have a fine complection.
To me, the eyes are the problem. They are not very well drawn.
They seem to point in a different direction than the rest of the face, as if seen from the side. But the more I look at it, the more I accept it.

Leif Gn