> The part about whether they should have been born or not, which was the ethical thing is what tears at me.

I gotta say... for me, this is close to murder. I realize these things are complicated but if it was a hybrid species, we might not know how close it was to us. It may have been close and it would absolutely be murder to kill a 100 day old child.

I think if it could potentially be murder you should just error on the side of caution.