Each year, dozens of children across the country die after being left in hot cars.
That's prompted several carmakers to create potentially backseat alarms that some argue could be as life-saving as a seatbelt.
Phoenix police responded to not one, but two, hot car deaths on the same day this past July.
Both babies were forgotten in cars with temperatures reaching into the high 90s.
The group 'Kids and Cars' says so far this year, 36 children have died this way.
Now, some automakers are rolling out new technology to help prevent these tragedies.
"They're absolutely heartbreaking," said Elsa Foley, Manager in OEM Business Development Group at Nissan.
Foley developed Nissan's new rear door alert system.
It monitors if a back door is opened before driving, and notifies the driver if the rear door is not reopened after parking in two different ways.
There are multiple phases of warnings and the first alert is right here on the dashboard.
After a few seconds, the next alert happens - the horn honks multiple times.
"...and that's what calls your attention back to say maybe I forgot something," Foley said.
Sen. Richard Blumenthal wants to see this kind of technology in every new vehicle. He introduced legislation that would require carmakers to install alerts. It has the backing of more than two dozen child and road safety groups.
"Consumers should want this product just as they do seatbelts and air bags," said Sen. Richard Blumenthal, D-Connecticut.
General Motors already has a backseat reminder available in several of its vehicles. Nissan is trying out its new alert in 2018 Pathfinders.
"To provide one more thing that can potentially help our customers...It's not a solution but it's I think a step in the right direction," Foley said.
One advocates say is a critical step toward saving lives.