Nahash

The father of Amasa, who was commander-in-chief of Abasolom’s army (2 Sam. 17:25). Jesse’s wife had apparently been first married to this man, to whom she bore Abigail and Zeruiah, who were thus David’s sisters, but only on the mother’s side (1 Chr. 2:16).

M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition
Children: Abigail, Zeruiah