I guess there is really alot to think about, If you feel that the other puppy is the right one for you and decide to go ahead on her then just be sure to have bile acid tests done, after 16 weeks of age. There is still not an exact understanding of how LS is passed on, but because the high occurance in yorkies, we know that there is a genetic link. A good breeder would have both parents fixed and no longer breed from that line. The whole idea is to quit breeding dogs that carry this or pass it on so that less future dogs and owners have to suffer through the heart break of ls and other liver problems. Most cases there is something that can be done and most LS dogs that have the surgery can live a normal life after, it is so sad to see a puppy sick with liver problems
Please just follow your heart and keep us posted best of luck with your decision