Genesis 30:3–4
3 Then she said, “Here is my servant dBilhah; go in to her, so that she may give birth eon my behalf,1 that even I may have children2 through her.” 4 So she gave him her servant Bilhah as a wife, and Jacob went in to her.
Genesis 30:9
9 When Leah saw that she had ceased bearing children, she took her servant Zilpah and hgave her to Jacob as a wife.