Hun-Joon Lee was bigger than life, his family says. The Whittier teen was always smiling, and although he had special needs and could not speak, he understood instructions.
When family members learned that Lee had been left on a school bus on a hot Friday afternoon, they thought he may have stayed there waiting for a cue.
The 19-year-old was found alone and unresponsive. Police could not revive him.
Local news from across Southern California
Lee, or Paul to those who knew him, had a severe form of autism. Leslie Perez's mom was his caregiver. She says her mom waited outside for Lee's bus to drop him off at 3:30 p.m., like she does every afternoon, but it never showed up.
Police found the adult school student lying in the aisle near the front of the bus parked in a Whittier school district parking lot. He was declared dead — less than two weeks before his 20th birthday — after lifesaving efforts failed.
His mother, Eun Ha Lee, was devastated.
"We live in a tomb now," she said through tears.
Lee's family said his bus picked him up at 8:30 a.m. that day. They don't believe he ever got off the bus.
"How do you forget a big boy and just leave him in the bus? It was a small bus," Perez said.
Police are calling the death suspicious, but they don't know yet how he died.
It's also unclear whether drivers with the bus company, Pupil Transportation Cooperative, are required to do head counts. Family members say a different bus driver had picked him up that morning.
His family believes the usual driver — who would say "Let's go, Paul" -- was not at work that day, replaced by another man.
On Sunday, the family came together to pray as they waited for answers from investigators.
The family has set up a memorial fund for Lee. Anyone wishing to donate can do so here.
Gordon Tokumatsu contributed to this report.