I am not a specialist by any means, but My grandmother recently went almost completly blind nearly after her cataract surgury and it was a build up of scar tissue on the eye. She went to a retinal specialist and she can now see and even drive again.
I would suggest seeing your eye doctor as soon as possible and discuss the next step.
Does she have any vison? If so large print books and magnifying glasses work wonders.
Good luck, I know this must be a very stressfull and hard time for both your mother and your family.