PCOS is an insulin caused disease.  Your cousin needs to stop all carbohydrate-rich foods which cause a spike in Insulin production.  I recently had a patient who was drinking 6-8 colas a day and suffered from PCOS.  Once she stopped the liquid sugar she was drinking the PCOS went away.  Alcohol, fruit juices, grains and starches all sweets and desserts are what create PCOS.  Getting off sweets is hard to do.  The herb Gymnema can help if taken regularly.