It is wrong make someone feel unimportant.
Malcolm is a child who his at his brother's recital, but he is mad at his brother.
Malcolm wants to get back at his brother.
Malcolm waits until after the recital to get back at his brother because he knows he practiced hard for it.
Malcolm walks out of the recital when his brother takes the stage.
Malcolm's brother accepts what Malcolm dishes out and apologizes for making him mad in the first place.
Malcolm's brother knows that he was mad at him but can't understand why he would ignore the recital.