The driver took off without helping the 16-year-old, who is now unconscious at Texas Children's Hospital.
Isaiah Rousey is in a medically-induced coma. Someone passing by saw his broken bike and stopped to find him injured.
His family said they're still trying to wrap their minds around the fact that the person who hit the 16-year-old left him for dead.
"You can't just leave the scene. You can't leave a human being that way. People won't even leave a dog on the road like that," Isaiah's aunt Roxan Gonzalez said.
Gonzalez said her family is in shock and disbelief.
They're struggling to understand how a curious teenager who loves life could wind up in a hospital bed with shattered bones all over his body and a brain injury.
Rousey's condition was caused by a driver who ran into him while riding a bike going east near 8311 FM-1960 between 2 a.m. and 4 a.m. on Monday.
His aunt said he shouldn't have been out at that hour, but he also should have been safe in his own neighborhood.
"He's a great kid. He's a good kid with a good heart. He didn't deserve that. No one deserves that," Gonzalez said.
The Harris County Sheriff's Office is working to figure out who hit Rousey. Investigators and his family are asking anyone with helpful information or video to come forward.
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