This is so cute of you. I wish I had a sister like you. Truly, sister are for each other. It is nice to hear that you are interested in helping your sister. More important that it has always been her dream. Well, being a surrogate is not a big task. If you are a mother already them you know how it feels like already. It is just the usual being pregnant for 9 months. Only that in this case the child is not yours. But you will pass through the same emotions and feelings. The morning sickness. Feeling tired more often and the stuffs. I personally am a profession surrogate. I have been a surrogate mother for 4 couples. So I can say it is not a hard task. Now that for you it is mot a job but it is because of love. I believe you will not have a hard time. Just live a healthy lifestyle and avoid drinking or smoking.