Genesis 30:3-5

Amplified Bible, Classic Edition

³ And she said, See here, take my maid Bilhah and have intercourse with her; and [when the baby comes] she shall deliver it upon my knees, that I by her may also have children.

⁴ And she gave him Bilhah her maid as a [secondary] wife, and Jacob had intercourse with her.

⁵ And Bilhah became pregnant and bore Jacob a son.