The Second Book of Adam and Eve 1
Author unknown, closely tied in origin and transmission to the First Book of Adam and Eve, likely from the same tradition and comparable date range (proposed from the early centuries AD to as late as the 5th-6th century). Continues the story of Adam and Eve's descendants down toward the time of Noah.
6As for Cain, when the mourning for his brother was ended, he took his sister Luluwa and married her, without leave from his father and mother; for they could not keep him from her, by reason of their heavy heart.
7He then went down to the bottom of the mountain, away from the garden, near to the place where he had killed his brother.
9But as for Adam and Eve, they came not together after Abel's funeral, for seven years. After this, however, Eve conceived; and while she was with child, Adam said to her "Come, let us take an offering and offer it up unto God, and ask Him to give us a fair child, in whom we may find comfort, and whom we may join in marriage to Abel's sister."
12Then Adam and Eve continued fasting and praying until Eve's time came that she should be delivered, when she said to Adam: "I wish to go to the cave in the rock, to bring forth in it."
13And he said, "Go and take with thee thy daughter to wait on thee; but I will remain in this Cave of Treasures before the body of my son Abel."
14Then Eve hearkened to Adam, and went, she and her daughter. But Adam remained by himself in the Cave of Treasures.