my mother is sufering from diabetes n kidney stones problem due to which she cannot fast

i have a question to ask.my mother is sufering from diabetes n kidney stones problem due to which she cannot fast during the month of ramzan and if she tries to keep a fast then she has a problem passing urine which makes her fall into bed soon after she breaks her fast .so we recommended her not to fast as she is suffering from this type of problem.she has decided that she will feed a poor beggar everyday same food a she eats whenever shes not fasting.kindly tell me is this decision made by her correct.cos she also feels sad by not keeping fast as this is the only month to fast and if she tries to fast she faces this problem.please give the answer to this problem.jazakallah.