Bilhah

Bilhah was a maidservant to Rachel, who was one of Jacob's wives. Rachel when realizing her sister Leah bore Jacob many children, while she bore none, gave Bilhah to Jacob, so she could have children through Bilhah, as that was a custom of that time and place. Bilhah bore two sons to Jacob, Dan and Naphtali. Later on, Jacob's oldest son, who was born of a different woman, Reuben, committed adultery with Bilhah.