Amber Rollins knows the dangers of children and hot temperatures all too well.

As the director of KidsAndCars.org for the past 20 years, a national child-safety organization, Rollins helps track the number of children who died after they were left—after they were forgotten—in a car.

Statistics gathered by KidsAndCars.org show that about one child in the United States dies every nine days from hyperthermia, a horrific condition that results in the body warming to fatal levels where organs fail. In Texas alone, 120 children have died of hyperthermia since 1991.

“The biggest challenge is no one thinks it can happen to them,” Rollins said, a mother herself. “We can talk to people about this until we’re blue in the face who just don’t think it can happen to them.”

Forgetting a child isn’t a matter of bad parenting or being a careless adult, but rather a memory lapse with tragic consequences.

In 2016, I wrote about a mother whose 3-year-old son died in a hot car after his grandmother forgot to drop him off at day care an August morning in 2008. (You can read her story here.) His death wasn’t the result of malicious intent by his grandmother, but a lapse in memory from his grandmother who rarely took him to day care. Dr. David Diamond, a neuroscientist who for decades has studied why parents forget their children, said it often happens because of a change in routine or due to fatigue or stress.

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Read more: Why do parents continue to forget about their kids in cars?

At the time of the story, 111 children had died in a hot car in Texas, including another family who forgot their 2-year-old as they attended a church service in North Texas. In the two years since, nine more children have died.

As Robert Lapus, the medical director of the pediatric emergency center at Children’s Memorial Hermann Hospital, told me then, children’s bodies aren’t as developed as adults and are more susceptible to heat. When heat stroke takes effect, their organs fail, they suffer from seizures and ultimately cardiac arrest.

It’s a tragedy Rollins said is entirely preventable.

To prevent more deaths, KidsAndCars.org has worked with lawmakers to introduce the HOT CARS Act of 2017, which would require the U.S. Department of Transportation to enforce that all new cars be equipped with various alert systems to remind adults of a child in the back seat.

It’s a no-brainer to Rollins, who noted that cars are already outfitted to remind their owners of when it’s time for an oil change, to buckle their seatbelt or alert them of low tire pressure.

“If people want to stop these tragedies, call their senators U.S. senators and representatives and talk to them about the HOT CAR Act, and to pass or co-sponsor the bill,” Rollins said.

The bill is currently attached to another that has passed the House and the Senate committee. It’s awaiting a vote on the Senate floor.

As the calendar rolls into the summer, Rollins pleads to remember the children who are most susceptible to heat.

“We have to keep this in the news and in people’s minds,” she said. “The numbers are not going down.”

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