2 Samuel 13:28-30

28Now Absalom had commanded his servants, saying, “Watch now, when Amnon’s heart is merry with wine, and when I say to you, ‘Strike Amnon!’ then kill him. Do not be afraid. Have I not commanded you? Be courageous and valiant.”

29So the servants of Absalom did to Amnon as Absalom had commanded. Then all the king’s sons arose, and each one got on his mule and fled.

30And it came to pass, while they were on the way, that news came to David, saying, “Absalom has killed all the king’s sons, and not one of them is left!”