Sleepy - Your sister sounds really worried, and understandably so. I don't know anything more, but I do know that 1 in 300 means she has a 299 in 300 chance of her bub not having Down Syndrome if it helps to look at it that way, and even 99 in 100 if it gets down to that. It will be a long few days for you all - I hope you're all OK and that you can find some more info.