That’s so nice of you. Sisters are always very caring for each other. Your post shows how much you love your sister. That’s so cute. Dear, there is not any problem in being a surrogate. That’s will help her emotionally and financially. The major with this treatment is cost. The services are a bit expensive. Most of the people can’t afford such expensive treatment. Your sister is also financially weak. You can help her to achieve her dreams. It will be costly if she appoints a surrogate from some agency or clinic. The main portion of your cost of treatment will be given to the surrogate. The procedure will not be the reason for this high cost. Now if you become her surrogate then she won’t need to worried about your diet. You can take good care of yourself as you have children. I am really glad that you are helping your sister. I wish you the best of luck for that.