Genesis 38:5

³  And she conceived, and bare a son; and he called his name Er.

⁴  And she conceived again, and bare a son; and she called his name Onan.

⁵  And she yet again conceived, and bare a son; and called his name Shelah: and he was at Chezib, when she bare him.

⁶  And Judah took a wife for Er his firstborn, whose name was Tamar.

⁷  And Er, Judah's firstborn, was wicked in the sight of the LORD; and the LORD slew him.