It was a terrifying situation for one family in Florence, after they went to pick up their son from kindergarten and he wasn't there.
The boy was found almost an hour later walking along a busy highway.
This boys' father feared he might have been kidnapped when he wasn't at school when he went to pick him up.
Now they're wondering how a bus driver didn't notice their son was on his bus even after police sent out a description of the little boy.
"Worst nightmare. We were really scared, we didn't know where he was."
Tommy Fuentes is describing the ordeal he and his wife Dawnee went through last week. Their 5-year-old son was no where to be found when they went to pick him up from Anthem Elementary School in Florence.
"I was devastated. Absolutely -- I've never been hysterical in my life but I was then," says Dawnee.
Their son and two other boys thought it would be fun to get on a school bus after school instead of waiting for their parents to pick them up.
The other boys got caught, but the Fuentes' boy wasn't, and ended up riding the bus with no one knowing where he was.
The school quickly went into lock down and called 911. All bus drivers were given a description of the boy -- but somehow the substitute driver didn't notice the boy was on his bus.
The little boy was eventually dropped off by the school bus in a neighborhood about a mile away from his home -- a neighborhood he's never been in before. And it was also 112 degrees that day.
The boy wandered onto the Hunt Highway, walking along the side of the road, until a Good Samaritan and then an ambulance crew stopped to help him.
"They saved his life by stopping. I mean who knows what could have happened."
The Florence Unified School District has put new policies in place to make sure this doesn't happen again by having more teachers out by the buses to monitor who gets on the buses.
An investigation is also going on to see if the bus driver did anything wrong in this situation.