Well, if it is true, its definitely a very personal thing that is entirely too taboo for the general public. I can't say that I agree with it, but then if two siblings that weren't reared together, meet and fall in love, is it just as bad? Morality is so subjective.
I understood the story. I was mentioning the not rearing together in reference to a German couple who met in high school, fell in love and later found out they were brother and sister, just adopted out. So, is that just as wrong and taboo as this story is?
The odds aren't very likely, but the German couple is a true story. As a matter of fact the man has been arrested on several occasions for it. And they have several children. I want to say that they even got married and refuse to divorce. Where I don't personally ever want to touch my brother, it is more of a cultural thing than otherwise. And in some cultures it's not as harshly viewed. Then there is the whole issue of double recessive genetics if they ever had a child.