Those weren’t hte only children conceived by Adam and Eve. Man and woman were created with pure genes- no mutaitons- (and htis has been confirmed by a secular genetic investigaiton which foudn that hte further they traced the mtdna back, the purer it became)- As such, inbreeding did not have the dire consequences that we have today, and children born to a sister brother relationship were not genetically altered liek htye woudl be today- hence the taboo today on relations between close relatives. As the genetic code became corrupted via mutations (brought on by sin mind you- before hte fall, there was no problem), there came a tiem when relations of close relatives was no logner a viable means of populating hte earth with viable offspring, and it was then forbidden.
Why Evolution is impossible-
Evolution: Possible or impossible:
http://www.creationsafaris.com/epoi_toc.htm
Ridiculous.
Looks like God intended to purify the Gene pool with the flood, and again at Jericho, but satan always seems to have a way.