Can one personality kill another personality? For a person with multiple personalities, can one personality murder or kill another personality such that the killed personality never surface again?

Did it ever happen or studied?
Far from being simply encoded in the genes, much of personality is a flexible and dynamic thing (Mischel &amp; Shoda, 1995) that changes over the life span and is shaped by experience (Roberts, Walton, &amp; Viechtbauer, 2006).
  Can Personality Be Changed? by Dweck


After searching for related case studies, this is the closest I could find: "Deathman, age 27, intervened when John, Gail and Diana argued." -- Four Cases of Supposed Multiple Personality Disorder: Evidence of Unjustified Diagnoses This women's multiple personalities fought each other (even though the authors doubt she had MPD). 

Perhaps "kill" is not the best word.