If the infection is really a bladder infection, then the following may help:
-boil fresh italian parsley with water for 5 minutes. Simmer for 20 minutes. Drink this as often as possible. This is the best treatment for bladder infection. I had many bladder infections in the past, and this helped me much more than the Antibiotic prescriptions. Indeed Antibiotics just made my problem worse..
In addition, she should drink lots of water, and occasionally she might add a dash of baking soda to water and drink it. This decreases the acidity of the urine, and hence the burning may be alleviated.