Genesis 4:20

And Adah bare Jabal: he was the father of such as dwell in tents, and of such as have cattle.

1. Lamech and his wife Adah had a son named Jabal.
2. Some of Jabal's descendants lived in tents, and some raised cattle.
3. This information was apparently recorded some years after the birth of Jabal - perhaps even after his death, the genealogical records being the basis of it.