Where I live, there are leash laws that apply to kitties as well.
If someone runs over and kills her cat, she should be charged with the death of the animal since her negligence caused the animal's death. A parent that lets their toddler run out into the street may be charged similarly...
It is not the driver's responsibility to avoid people's pets running around on a highway. I was tought that if a dog runs out in front of me, I should apply the brakes, but just run it over to avoid any other type of accident, such as swerving and possibly causing a bigger problem.
Her privelage to own pets should be revoked since she is obviously mentally unstable and she should possibly be charged with threatening vital harm to a minor.