John Gill Commentary 1 Chronicles 2:16

"and their sisters were Zeruiah and Abigail. And the sons of Zeruiah: Abishai, and Joab, and Asahel, three." — 1 Chronicles 2:16 (ASV)

Whose sisters were Zeruiah and Abigail .
&c.] That is, sisters of David:

and the sons of Zeruiah; Abishai, and Joab, and Asahel, three ;
all valiant men and captains in David's army; their father's name is nowhere mentioned.