Here’s a familiar story:
Plot, plot, plot, character does something, plot, plotty plot plot, character does something else, plot, character dies and it’s so fucking tragic. Why can’t you see how tragic this is?!?
Except that it’s not tragic. Because, according to my super-technical summary up there, that character didn’t do much of anything. The plot did stuff, but the character was mostly just along for the ride. They were driven, not driving.
I call this the bystander effect. Too often characters in stories that die are not important. They were either plot devices or someone with so little impact on the other characters that they might as well have had a sign around their neck reading I exist only to provide the protagonist with a tearful moment. If you’re alert, you can see the death coming because that character serves no other purpose.
It’s no good just telling people that an event is tragic. No one likes being led around by the nose. And your audience is smart. They will know when they are being forcibly led, and they will resent you for it like kids being guilt tripped into eating their vegetables by Mom’s descriptions of starving people. And then they stop reading.
Here’s how you make a character’s death count: make them an actual character. They should do things with other characters that have emotional weight. They should have an affect on the world around them. They shouldn’t just be a Feels Delivery System from central casting.
There are shorthands you can use for this–mostly family relationships–but be careful. You might think that your protagonist’s brother dying is a big deal, but unless he had something to do he might as well be a random pigeon that got knocked out the sky. It’s got a hell of a lot more impact if you show your protagonist’s older brother looking out for her and then dying. Then she has to carry the weight of his death as well as the fear that no one can help her now. It makes her hesitate before getting close to people because he already sacrificed himself to save her and why does everyone she love die?
All the feels. Just because her brother was a person with a real impact on her life instead of a random bystander wearing a tag that said “main character’s brother who dies conveniently lolz”.
Remember: every character in a fully realized world is the protagonist of their own tale. They have things that they want. So they will interact with your protagonist with that in mind. They’ll try to move things in their direction. There should be the sense that, if you suddenly stopped following the main character and started following this other guy, the story would not grind to a halt. It might be a different story–and in the case of Brother, likely a shorter story*–but it would still be a story.
Don’t tell me to feel. Make me feel by giving me a reason. And I’ll be with you until the closing pages.
*Also a tragedy.