I think the people arguing for the wole 'WE SHOULD KILL THE UNDESIRABLES NATURAL SELECTION FTW RARGABLARGABLARGH!' are being a little extreme. We've emerged from the primoridial soup aaages ago (or whatever), got our shit together and conquered the ENTIRE PLANET, and we're now exploring space.
I think natural selection has pretty much gone out the window by this point. Call me wrong or whatever but I think that we're doing fine as it is, the contest is over, there's pretty much NOTHING more natural selection CAN do, the contest is over, WE WON. You wouldn't stay up all night studying if there were no exams/tests/whatever to do, would you? Of course there's going to be folk who can't walk, or can't think as well as most, but they can be useful, productive members of society; people who can't walk still have perfectly good minds, people with autism or whatever can still do manual labour, who are YOU to decide who lives and who dies? this single-minded sacrificing of innocent lives for some non-important 'goal' of 'preserving the gene pool' is kind of outdated.Even Darwin was a humanitarian.
Sure, this would have been the way to go back when we were fighting off animals and all that assorted crap back in the caveman days, but we have developed technology and medicine to a point where pretty much anyone can do regular stuff (e.g. wheelchairs, bionic limbs, etc), and there is no reason why these perfectly innocent children would be put to death. People cannot control their genes. Plus, if we were to kill EVERYONE with a faulty gene, that's pretty much 3/4 of the planet dead right there.
As long as she can CARE for all those children, why should YOU care?
TL;DR: People can do what they want, Natural selection is dead, People are awesome ^_^