2 Samuel 3:5 (BSB)

and his sixth was Ithream, by David’s wife Eglah. These sons were born to David in Hebron.

From 2 Samuel 3. Also in the ESV.

Commentary on 2 Samuel 3:5

• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on 2 Samuel 3:1-6: Here is, I. The struggle that David had with the house of Saul before his settlement in the throne was completed, Sa2 3:1. 1. Both sides contested. Saul's house, though beheaded and diminished, would not fall tamely. It is not strange between them, but one would wonder it should be a long war, when David's house had right on its side, and therefore God on...
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on 2 Samuel 3:5: And the sixth, Ithream, by Eglah David's wife,.... Who also is not spoken of in any other place; only, in a like chronological account as the former, it is remarked that the mother of this only is called David's wife; the reason of which is supposed to be, either because she was a person of no note, and had nothing else to distinguish her; but...
• Jamieson-Fausset-Brown (Reformed), Commentary Critical and Explanatory on the Whole Bible on 2 Samuel 3:5: Eglah David's wife--This addition has led many to think that Eglah was another name for Michal, the first and proper wife, who, though she had no family after her insolent ridicule of David (Sa2 6:23), might have had a child before.
• Geneva Bible Notes (Reformed), Geneva Bible Study Notes on 2 Samuel 3:5: And the sixth, Ithream, by Eglah David's wife. These were born to David in Hebron. (c) Within seven years and six months.