Genesis 38:26

Judah realised his duty. He should have given his son Shelah as a wife to Tamar. If Shelah did not do the duty, the duty was on Judah. Judah was Er’s nearest relative apart from Shelah.

v27 The time of the birth came. Tamar realised that she had two children in her. v28 One child put out a hand. And the nurse who helped at the birth took the hand. She tied a red string on his hand. She said, ‘This one came out before the other one.’ v29 But he pulled his hand back and his brother came out. And the nurse said, ‘You certainly broke out!’ Therefore he was called Perez. v30 Then his brother came out and the red string was on his hand. He was called Zerah.