Casualties of Fiction

I'm working on some manuscript changes suggested by an editor in the hopes I'll get offered a contract. She asked me to kill someone. Not a main character of course, but a close relative of my beloved heroine. It hurts. These people are important to each other. It's going to change all their lives.
And that leads me to the challenge of writing in this change. Such an emotional toll will echo through the rest of the book. An undercurrent of sadness and loss must now mute the final victory. Feelings of guilt and failure will need to be shared and expressed. The stakes are higher now. The happily ever after will only be won with a price.
Why ask me to do this? Why kill that good person? Why kill that innocent? Must my heroine suffer so much?
The answer is yes. When I first saw what this editor wanted me to do I fought against it mentally. I took a few days to think about it before agreeing to make the changes. Deeper emotions will be explored. The bonds of love will be forged in the hot fires of grief and shared hardships. It will not come easy. And for that, this novel will be a better book. The characters will have added layers of ties to each other and the secondary characters in the book. The good guys will be less perfect. They're going to make a mistake and someone will die because of it.
It's difficult to change so much after a novel is completed, but by working with this editor, I have learned so much about creating internal and external tension.
I promise to tell you more about this novel should I get a contract. I can tell you, I think it's going to be good.