Keep in mind that any decision you make will impact your first child. Illnesses will be passed from child to child, Pseudamonas, Cepacia, ect. If one is much sicker than the other, it drags the healthier child down too over time. I've seen it happen many times. This is from the perspective of a mom w/CF, 2 kids. I dont really believe in selecting embryos, but if you look at from the perspective of protecting BOTH you children, especially the already existing child whom you presumably love like crazy, I think the decision is easier. Its not that you are saying that your first child is in any way less of a wonderful amazing person because they have CF, but by doing selection for your second child, you can can choose to protect BOTH. Frankly, we decided to adopt since it didnt make sense to me to shorten my life span with a pregnancy, therefore sacrificing my lifespan for the very thing (family) I was trying to create.