FORT WORTH, Texas -- The parents of 3-year-old Ke'Andre Goodman say he worked his way into an unlocked car Friday afternoon. He then couldn't get out and ultimately died inside.

"Its been really tough," said Timothy Goodman, Ke'Andre Goodman's father. "And the way it happened ... has been eating us alive."

Goodman's death marks the seventh child to die inside a hot car in Texas, which is half of the total deaths in cars nationwide. In response, Cook Children's Medical Center is sending a clear message.

"Even on a cloudy day like this, the inside temperature of a vehicle can get up to twenty degrees or more in just a few minutes time," said Dana Walraven, the community health outreach manager for the hospital.

A white Honda parked outside the hospital Monday morning is equipped with special thermometers. Although the outside temperature reads 81 degrees, inside the vehicle it's closer to 96 degrees and rising.

"Children heat up much faster than adults and their bodies can shut down when their in that heat for an extended period of time," Walraven said.

The demo car served as a reminder for parents like Deirdre Lacey to stay vigilant.

"Extreme hot, suffocating," Lacey said. "I'm scared. I'm scared for anyone that could forget that their precious precious baby is in the back seat."

The hospital recommends leaving a wallet, keys, even a shoe in the back seat -- anything to keep you from forgetting a young one in the back seat.

According to national statistics kept since 1998, more than half of children that died from heatstroke in a vehicle were forgotten by a caregiver; another 28 percent were playing in an unattended vehicle.

That's something Goodman's parents say led to their sons death.

"I never expected this to happen to us, ever," Goodman said. "Because we stuck together so close all the time... God had a reason for him to call him home, that's all I can think of."

While no criminal charges have been filed against the Goodmans, we do know that the remaining of their six children have been removed from their home.