Cain and Abel?

It was always explained to me that in that time people lived much longer than we do. Hundreds of years. And if Abel married a much younger great niece then they would have been far enough apart genetically to avoid any inbreeding problems. If you can understand that.
I'm not sure what I myself believe. It's probably a mix between creationism and evolution. Devine intervention in the evolutionary process, so to speak.

 

That is true it could have easily been a great niece.