Genesis 35:22

22 It happened, while Yisra'el lived in that land, that Re'uven went and lay with Bilhah, his father's concubine, and Yisra'el heard of it. Now the sons of Ya`akov were twelve.

Genesis 35:22 In-Context

20 Ya`akov set up a pillar on her grave. The same is the Pillar of Rachel's grave to this day.
21 Yisra'el journeyed, and spread his tent beyond the tower of `Eder.
22 It happened, while Yisra'el lived in that land, that Re'uven went and lay with Bilhah, his father's concubine, and Yisra'el heard of it. Now the sons of Ya`akov were twelve.
23 The sons of Le'ah: Re'uven (Ya`akov's firstborn), Shim`on, Levi, Yehudah, Yissakhar, and Zevulun.
24 The sons of Rachel: Yosef and Binyamin.
The Hebrew Names Version is in the public domain.