I don't think any more parental figures will die because in book 6 Harry realised that he had to fight for himself and he couldn't let others stand in his way to Voldemort.
Perhaps Ron or Hermione or both will be badly injured or die. Harry would probably lose the will to live and sacrifice himself to destroy Voldemort.
I think if Harry goes down, Voldemort will go with him. JK wouldn't let Voldemort win....would she?