The Biblical text is pretty clear that Adam and Eve’s children were conceived after the fall.

The birth of Cain and Abel occurred after the Fall of Man, and after they were banished from the Garden which is described in Genesis 3. Genesis 4 is where it says, "And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the Lord. And she again bare his brother Abel." Therefore, the birth of their two sons, Cain and Abel, occurred after they had left the Garden of Eden and were living outside of it.

In Genesis 5:4, after the birth of Seth, the Bible says, "After he begot Seth, the days of Adam were eight hundred years; and he had sons and daughters."

The Biblical text is pretty clear that Adam and Eve’s children were conceived after the fall.

The birth of Cain and Abel occurred after the Fall of Man, and after they were banished from the Garden which is described in Genesis 3. Genesis 4 is where it says, "And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the Lord. And she again bare his brother Abel." Therefore, the birth of their two sons, Cain and Abel, occurred after they had left the Garden of Eden and were living outside of it.