I just read your post and I really don't think that fasting for one daywould cause her liver to become hard.
Have you tried Dr. Schulze 's liver/gallbladder cleanse? It is wonderful. My thought is she needs to do a Bowel Cleanse first then liver cleanse and then the kidney cleanse.
Often we have detox symtoms and people then stop out of fear when in actuality it is a good thing. YOu WILL have symptoms of detoxing if your liver is toxic. coffee enemas are great for this.
If you are interested I can give you more information on those protocols.