LAS VEGAS -- Metro police said the body of Jason Rimer, 4, was discovered inside a vehicle Monday morning in the driveway of his home.

Friends and church members held a vigil for the family Monday evening.

Members of his family's Mormon church came out in a show of support.

Jason was the youngest child of a family with eight children, seven brothers and one sister.

There are many unanswered questions in this case.

Metro police said they are trying to figure out how the boy got in the car and why the boy was unattended.

“Words can't express their pain, the anguish, the shock, absolute sadness that the family is feeling at this time,” said family spokesman Michael Gonzalez.

Gonzalez said Jason's older brother found him at about 8:30 a.m. Monday in the back area of their Chevrolet Suburban SUV.

“I do know he had been in there for some time and discovered this morning. With the hustle and bustle of any large family of seven is running, I can just imagine. Any parent can understand, you can have a slight oversight,” Gonzalez said.

Investigators are trying to figure out if heat was a factor in his death. Police said his parents were at home at the time of the discovery, but they are still investigating what role they might have played.

“We're looking at the circumstances -- why that child was left in the vehicle, as far as how long the child was left in the vehicle. We don't have that at this time,” said Lt. Ray Steiber of Metro’s Crimes Against Youth and Family division.

A neighbor who asked not to be identified said she was stunned to hear the boy had died.

“This is a deadly situation. Nobody should leave a child in car, not one minute, not all day or overnight. I'm still in shock,” she said.

Metro has not pressed any charges against the family.

The family has set up a trust at Wells Fargo in Jason’s name.