I found this story today while surfing.
Daily News - We're twinseperable!
The parents of these little boys were faced with the decision to allow one of the boys to die while in the womb and risk the health of the other or end his life sooner and likely save the other. They made a choice I would not have made and chose to end his life surgically.
As the story goes they tried to cut the umbilical but found it was two thick for them to cut, so they cut the placenta in half so as to hopefully spare the "healthy" twin. Much to their surprise the next day he was alive and kicking and to their even greater surprise 5 weeks later he came out all nice and healthy. Now that is something to celebrate, with all odds stacked against him, he is alive and well.