[ShadowAce]

...Adam and Eve were the first and only two people on Earth. They had two sons, Cain and Abel.

Not entirely correct.

Don;t forget Seth. Also, Scripture mentions that Adam had other sons and daughters before he died at the age of 930. It is possible that Cain took a sister as wife.

[Netizen]

Don;t forget Seth. Also, Scripture mentions that Adam had other sons and daughters before he died at the age of 930. It is possible that Cain took a sister as wife.

But, wouldn't the sister be living in the same household and not in a different town/land?