David did not discipline his son Adoniyahu, with the result that he grew up rebellious. Adoniyahu died as a result of his trying to usurp the throne from King Solomon (in chapter 2). David's son Avshalom, also mentioned in this verse, was equally rebellious and also met a grisly fate as a consequence of his actions (in 2 Samuel 18). Rashi on our verse explains that if a person withholds rebuke from his children, then he is ultimately responsible for their deaths.