And the sixth Jethraam of Egla the wife of David: these were born to David in Hebron.

and the sixth is Ithream, of Eglah wife of David; these have been born to David in Hebron.

And the sixth, Ithream, whose mother was David's wife Eglah. These were the sons of David, whose birth took place in Hebron.

And the sixth, Ithream, by Eglah David's wife. These were born to David in (c) Hebron.
(c) Within seven years and six months.

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 the same may be said of the two foregoing; or because she was his beloved wife, his heifer, as her name signifies; hence the Jews (y) take her to be Michal his first wife, whom he greatly loved, and who, though she had no children after her contempt of David for playing before the ark, unto the day of her death, yet might have before: but it should be observed, that as yet she was not returned to David in Hebron; and when she was returned, did not seem to continue there long enough to have a son there; and besides, being his first wife, would not be reckoned last; but still more foreign is another notion of the Jews (z), that she was Saul's widow, who though she might not be married to another might be married to a king, as David was; and this they suppose receives some confirmation from 2-Samuel 12:8; but after all it may be this phrase "David's wife", as some have observed, by a figure the rhetoricians call "zeugma", or "hypozeugma", is to be joined to everyone of the women before mentioned, 2-Samuel 3:2, who were his wives, and so called to distinguish them from his concubines, by whom he had sons also. Polygamy, or plurality of wives, which David gave into, is no favourable part of his character.
(y) T. Bab. Sanhedrin, fol. 21. 1. Hieron. Trad. Hebrews. in 2 Reg. fol. 77. F. (z) In Kimchi & Ben Gersom in loc.

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 (2-Samuel 6:23), might have had a child before.

Eglah - This is added, either because she was of obscure parentage, and was known by no other title but her relation to David: or, because this was his first and most proper wife, best known by her other name of Michal, who, though she had no child by David after she scoffed at him for dancing before the ark, 2-Samuel 6:23, yet might have one before that time. And she might be named the last, because she was given away from David, and married to another man. Six sons in seven years. Some have had as numerous an offspring, and with much more honour and comfort, by one wife. And we know not that any of the six were famous: but three were very infamous.