2 Samuel 16:9

Abisai : the son of Zeruiah, David's sister; brother of Joab

Zeruya : daughter of Jesse; sister of David; mother of Abishai, Asahel and Joab

2 Samuel 18:11

Yoab : son of Asaph; record keeper of King Hezekiah,son of Zimmah one of the Levites of Gershon whom, along with his son Eden, King Hezekiah assigned to supervise the cleansing of the temple,son of Obed-Edom; a Levite gatekeeper whose descendants returned from exile,son of Joahaz; record keeper of King Josiah