My Sister's Keeper, anyone seen or read this?

I love Jodi Picoult and have read many of her things. This one, like most of hers, was very interesting to read. I do not agree with parents having/raising a child to safe the life of one they already have. What if something were to happen to the second child later in life where the same thing were to happen? Should the parents continue a chain reaction and just keep producing children in order to save an already existing one? I think not.