9-year-old boy survives horrific chain-reaction crash that killed his father off Beltway

HOUSTON, Texas (KTRK) -- A 9-year-old boy miraculously survived a crash that killed his father last week off the South Beltway near Sabo Road.

The boy's family says they are upset after ABC13 uncovered the police investigation into the crash was mishandled.

Kevin Medillin made it out of that crash with not so much as a broken bone, but his family says he's different -- quiet, confused, and clearly traumatized.

ORIGINAL REPORT: 18-wheeler rams into 6 cars waiting at stop light in SE Houston, killing 1 and injuring 2, HPD says

The Houston Police Department is investigating a fatal crash involving an 18-wheeler and at least six vehicles overnight.

The family said the boy's father, Francisco Medillin, shielded him with his body upon impact. They say Houston police made the whole thing 10 times worse through shoddy detective work.

Kevin finds it much easier to draw than talk about how his life has changed.

"He is trying to go day-by-day, sometimes he doesn't talk at all. He doesn't sleep. He's not eating well. He is just devastated," said Tammy Contreras, who helped raise Kevin.

She says minutes before the crash, she met with Francisco, who was picking Kevin up for the weekend.

"I wish I could have talked to him for five more minutes. That could've saved his life," Contreras said.

At the scene last Friday, HPD determined an 18-wheeler was at-fault -- claiming that's what witnesses told investigators. Except there was a problem -- surveillance video obtained by ABC13 on Monday showed otherwise.

READ MORE: Video captures chain reaction crash that killed a father in front of his son in southeast Houston

A man was killed during a massive crash over the weekend when several cars were hit at a stoplight on South Sam Houston Parkway East at Sabo Road.

"As a private investigator myself, I went to the store. I have the video on my email. It was that simple," Contreras said.

The video shows the 18-wheeler in question stopped at a red light while Francisco's car is thrusted into the back of it. From a different camera, you can see it was a black Lexus that plowed into his car, sending it airborne.

"I want answers. They need to do something. Everyone should be outraged," Contreras said. "What if this was your family?"

ABC13 gave HPD the video on Monday, but they waited until Wednesday to publicly call off the search for the 18-wheeler.

SEE ALSO: HPD now says 18-wheeler driver wanted in deadly crash didn't cause it

They now say the driver of the Lexus, who was transported to hospital in critical condition that night, caused the crash.

"I am paying them with my tax dollars," Contreras said. "They couldn't do their job?"

Contreras says the accountability she demands is not for her, its for Kevin -- a boy whose last moments with his father were in a car, terrified and flying through the air.

"My concern is Kevin. I need to give him answers. I need answers. I need to know who is responsible. Why? Someone needs to be in jail," Contreras said.

HPD said there are no pending charges, though the investigation is ongoing. At last check, they said they have not interviewed the alleged at-fault driver and say she is still in the hospital.

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