You have been given some good advice,
I would just like to add, if your sister hasn't had her back checked by a good osteopath or chiropractor she should get it checked now.
It seems to me one of your biggest challenges is to convince her natural threapies will work, she is fortunate to have you encouraging her, get her to read all she can to get a better understanding of how to turn her health around, and help her realise there is no quick fix, it took years to get to this stage and it will need patience and perserverance to regain her health.