2 Samuel 13:30

“And it came to pass while they were in the way, etc.] On their road homewards, before they got to Jerusalem: that tidings came to David; perhaps brought by one who was at the entertainment, who upon seeing Amnon smitten, immediately rose up and fled with the news of it to David: saying, Absalom hath slain all the king’s sons, and there is not one of them left; which he might suppose was the design of Absalom, and was done before that time; however, so it was ordered in Providence, that David, that rejoiced at the news of the death of Uriah, might be terrified with the tidings of the death of all his sons; and for a while it was as if it was really so, which occasioned the following behaviour…”

“tidings came to David, saying, Absalom hath slain all the king's sons--It was natural that in the consternation and tumult caused by so atrocious a deed, an exaggerated report should reach the court, which was at once plunged into the depths of grief and despair. But the information of Jonadab, who seems to have been aware of the plan, and the arrival of the other princes, made known the real extent of the catastrophe.”