And that's not their only question as they ponder the chain of events that led to a metal fragment flying off a truck and into the stands, where it struck and killed little Sebastian Hizey.
The boy's father spoke out about the accident for the first time Sunday, even as the final two Monster Jam performances of the weekend were taking place in Tacoma.
At times, it's hard for his parents to keep it together - there's so much sadness, so much grief, a bit of anger.
And permeating all of it is the feeling that this bizarre death happened to the wrong person at the wrong place at the wrong time.
"We were having a blast that night," says the boy's father, Jessie Hizey. "And one thing happened, and he was gone."
Jessie says he will never be able to shake what happened that night. He'll always wonder why one of his children died in such an awful way.
"Wish we weren't there," he says. "Wish I was standing up; perhaps it would have missed him. A lot of things could have gone completely differently and he'd still be here."
Photo shows a metal part that spectators say flew from the truck and apparently struck the little boy. It was found in the stands near the boy's seat.
It's believed at that point, metal debris spewed up into the stands.
After the accident, a spectator found a metal ring in the stands near the spot where little Sebastian had been hit. The metal ring is about the size of a Frisbee, weighing 10 pounds or so. The family believes this is what hit their boy.
Jessie Hizey said the trip to the monster truck show was a family event that everyone was looking forward to. Sebastian's two sisters and a brother were there, too.
They saw the aftermath.
"They grieve just like the rest of us," Jessie Hizey said. "They had to see the same thing that we saw. They don't understand it any more than we do."
Family members say little Sebastian was a shy boy who loved creative coloring, board games and just being a kid.
A big loss - with so many tough questions that will never be answered.
"Why were we the chosen one? Why did this happen?" asks Phyllis Dwyer, Sebastian's stepmother. "It's a question that keeps playing in my head over and over again. I thought we were doing something fun for the family."