Something I see fairly often in stories:
Some huge life-changing event has happened—whether to the protagonist, to someone close to them, or to the world.
And that event drives the plot, but the protagonist (and other affected characters) don't seem to be particularly emotionally affected by it.
For example: Say the author wants to write a story about a character receiving a mysterious gift. So the protagonist's parents die in a car crash, and the protagonist inherits (say) a mysterious box.
And the story is all about the character being intrigued by the box and trying to figure out how to open it, and then how to use the alien artifact that's inside. And the author is so focused on telling the story they want to tell that they completely forget that when a real person's parents die in a car crash, the person is usually emotionally devastated.
So: by all means, have big life-changing things happen to your characters. But make sure that you think about, and portray plausibly, the emotional consequences.
And if you don't want your protagonist to be grief-stricken throughout the story, then don't kill their parents at the start. There are plenty of other ways to receive a mysterious inheritance.
Note: In case this isn't clear, my point here is not about the deaths of a character's parents; that's just a made-up example. More often the event in question is the death of a child, or an alien invasion, or a pandemic, or various other significant events.