Sarah McIntosh, of Kansas City, North, buckles Ethan McIntosh, 13 months, into his car seat. Sarah uses a stuffed dog with a "Got Ethan?" tag sitting in the front seat to remind her that Ethan is in the car with her.
KANSAS CITY — Forty-nine children in the United States died of heatstroke after they were left in hot cars last year, a grim record.
But as child-welfare groups try to prevent more deaths with information campaigns and as inventors work on technical fixes, both efforts founder on a hard reality: Good parents don’t think it can happen to them.
It can, experts and statistics say, and new recommendations on rear-facing car seats could make the problem even worse.
The parents of more than half of almost 500 children who died from being left in hot cars from 1998 to 2010 simply forgot their kids were in the vehicles, experts report.
At least five children have died so far this year, including three in May in southern states. Two died on May 25, including a 5-month-old girl in Kennesaw, Ga., whose caretaker forgot she was in the car.
Janette Fennell of Leawood, Kan., compiled the numbers for Kids and Cars, her home-based nonprofit, which has become a national leader in child car safety.
"They think of the people this happened to as monsters, and they don’t put in place the safeguards you should," she said. "If you have the ability to forget your cell phone, you can forget your child."
Kids and Cars will soon print "Look Before You Lock" warning tags that will go into take-home kits that hospitals give new mothers.
Safe Kids USA recently launched a "Never Leave Your Child Alone in a Car" campaign.
Ethan McIntosh's mom uses this stuffed dog with a "Got Ethan?" tag as a reminder for her to check the back seat where her 13-month-old rides.
A recommendation that the American Academy of Pediatrics issued in March might keep kids safer in crashes but make it more likely that they’ll be forgotten in a car. The academy now wants parents to put children in rear-facing car seats in the backseat until they’re 2 years old or 30 pounds, an increase of one year or 10 pounds.
The last time experts pushed a new campaign to put more children in rear-facing seats — in the 1990s, to cut the chances of being killed by air bags — the number of children who died in hot cars spiked.
In fact, more kids died from being left in hot cars than had died from air bags, Kids and Cars reports.
David Diamond, a psychology professor at the University of South Florida, shares the worry that extending the time children sit in rear-facing seats will mean that more of them will die of heatstroke when their parents forget they are there.
Almost 90 percent of children who died of heatstroke in cars from 1998 through 2009 were 3 years old or younger, Kids and Cars reports, and about three-quarters were 2 and younger.
In a multitasking world, Mr. Diamond said, their enemy can be the human brain’s tendency to focus on what it is doing at the moment.
He likens it to putting a cup of coffee on your car roof while you pull out the keys and get in. It is easy to forget the coffee until it spills down the windshield when you drive away.
Stress, lack of sleep, and changes of routine add to that tendency, he said. A parent might pay so much attention to the stress or what lies ahead at work that he drives right by the day-care center almost in autopilot mode, Mr. Diamond said.
Mary Parks, whose 23-month-old son, Juan, died in her car in 2007, never thought then that she could do such a thing.
The accountant from Blacksburg, Va., tells people her story in memory of her son:
Juan and his 4-year-old brother, Byron, had been sick for weeks, so she had been losing sleep. She was usually the one who stayed home with a sick child. But this time she left Byron home with her husband and took Juan to day care, or so she thought.
"It’s not really that you forget," she said. "I call it misremembering."
Somehow she drove straight to work but was sure she had dropped Juan off at the nearby day care. Usually Byron, who was talkative in the car, was also with her, but Juan just quietly went to sleep in the car seat behind her.
At the parking lot at work, she grabbed her purse from the front seat, went in, and had a normal day. She even told others she might have to take off early to pick up Juan at day care because he was still somewhat sick.
When she got there, the staff told her that Juan had never arrived.
"I took off running to the car," Ms. Parks said. She found Juan limp and pale. On a September day with temperatures in the 80s, she knew it was too late.
She went into shock and could not think or function normally for weeks, she said. Prosecutors later charged her with manslaughter and felony child abuse, she said, and two years passed after Juan’s death before they dismissed all charges.
Ms. Parks found Kids and Cars and met other parents who had lost children the same way.
She sometimes talks to groups, trying to explain the dangers in memory of her son and to prevent other child deaths.
Many people think she is a monster, Ms. Parks said. Some say they understand it could happen to anyone. She said few take a middle position.
From her Leawood, Kan., base, Ms. Fennell has fought unsuccessfully to get car manufacturers to install sensors that would beep if a baby is left in the car, like they do when a driver accidentally leaves the lights on.
Add-on devices can signal when a baby is left in a car, but few people buy them, she said. "No one thinks it can happen to them," she said, although it has happened to doctors, scientists, and others who loved and doted on their children.
At the Lake of the Ozarks in Missouri, inventor Bob Steffen has stopped making a $30 device he sold that played "Twinkle, Twinkle Little Star" when the car stopped. But he says better things are under way.
He is working with a car manufacturer to create a system in which a new marker on the dash will light up on a wireless signal from a device in a child car seat, he said, and an alarm will beep if the child is left in the backseat. He also intends to soon put out a phone app that will pick up the signal.
In a kind of stealth marketing, those alerts also would go off if the child unbuckles the car seat and gets loose, he said. A recent study found that many children 3 and younger unbuckle themselves while the car is in motion, putting them at a slightly higher risk for serious injuries.
The unbuckling alert will let companies sell a product to deal with a problem people admit as well as one they don’t, Mr. Steffen said.
But Cherie Sage, director of Safe Kids Kansas, said that for liability reasons car seat manufacturers discourage putting devices they haven’t tested in car seats. Safe Kids emphasizes low-tech solutions like keeping your purse, your cell phone, or another essential item on the floorboard in the backseat.
Sarah McIntosh, 25, of Kansas City, Mo., says she learned of the danger of forgetting a child from Kids and Cars, and she believes it can happen.
When she puts her 13-month-old son, Ethan, into his rear car seat, she puts a stuffed puppy in her front passenger seat that has a tag on it that says, "Got Ethan?"
She also puts her purse and diaper bag in the backseat, she said.
But people have to believe it can happen to them to do things like that. For most parents, Ms. Fennell says, that day has not yet come.