Genesis 30:15-17

But Leah answered, “Is it a small thing that you have taken my husband? Would you take away my son’s mandrakes also?” So Rachel said, “Jacob shall sleep with you tonight in exchange for your son’s mandrakes.” When Jacob came in from the field in the evening, Leah went out to meet him and said, “You must sleep with me [tonight], for I have in fact hired you with my son’s mandrakes.” So he slept with her that night. God listened and answered [the prayer of] Leah, and she conceived and gave birth to a fifth son for Jacob.