Five sons of Michal - whom she brought up - Michal, Saul's daughter, was never married to Adriel, but to David, and afterwards to Phaltiel; though it is here said she bore ילדה yaledah, not brought up, as we falsely translate it: but we learn from 1 Samuel 18:19, that Merab, one of Saul's daughters, was married to Adriel.
Two of Dr. Kennicott's MSS. have Merab, not Michal; the Syriac and Arabic have Nadab; the Chaldee has properly Merab; but it renders the passage thus: - And the five sons of Merab which Michal the daughter of Saul brought up, which she brought forth to Adriel the son of Barzillai. This cuts the knot.
Rizpah - See the marginal reference. A foreign origin was possibly the cause of the selection of Rizpah‘s sons as victims.
Sons of Michal - An obvious error for “Merab” (1 Samuel 18:19 note).