So far this year, 23 children have lost their lives in hot cars. Eleven of them were accidentally left in the vehicles by their parents or caregivers, and 12 were playing in cars and got trapped. Here are their stories.

March 8: Payton McKinnon, 17 months old, of Fort Myers, Fla.
Payton's father picked her up from daycare for a doctor's appointment early in the morning and returned to work at 11:09 AM, at which point he accidentally left Payton in the vehicle. When he left work shortly after 3 PM, he discovered his mistake. Source

April 18: Sofia Wisher, 7 months old, of Antioch, Calif.
The family pulled up to their home late Saturday after doing laundry at a relative's home. Each parent thought the other would be taking Sofia inside, but neither did. The next day, Sofia's father drove to the gym, not knowing the infant was in her car seat, lifeless, the whole time. Source

April 23: Joseph Chatmon, 21 months old, of Forsyth, Ga.
Joseph's mom forgot to drop the toddler off at daycare and accidentally left him in his car seat all day while she was at work at an elementary school. He was not discovered until she left work late that afternoon. Source

April 29: Brianna Jones, 7 months old, of Dallas, Tex.
A family friend was supposed to take Brianna to a daycare center after running errands, but forgot. Brianna was accidentally left in a hot car for more than four hours in the driveway of the friend's home. Source

May 5: Juan Ramirez, 3 years old, of Del Rio, Tex.
Juan snuck into the family car unnoticed. It was three hours from the time the boy was last seen alive to the time he was found inside the vehicle. Source

May 15: Gavin Demarest, 2 years old, of Manchester, Tenn.
Gavin had been playing outside with other children, and when it began to rain, the other kids came inside. When Gavin's father noticed that Gavin was not with the other children, he began searching for him. Gavin was found buckled in his car seat in the unlocked family car. His father said his son was able to buckle the main buckle but was not strong enough to unbuckle it. Source

May 26: Atrinity Hasbell, 2 years old, of Meeker, Okla.
A friend was supposed to drop the young girl off at daycare, but forgot. Atrinity was left in a hot car in the parking lot of the friend's workplace all day. Source

May 26: Maddison Jones, 9 months old, of Columbus, Ohio
Maddison's 70-year-old great-grandmother forgot to bring the baby into the daycare where she volunteered. Maddison was left in the car for four hours. Source

May 27: Alexander Morales, 18 months old, of Fort Worth, Tex.
Alexander's grandmother was supposed to be watching him as his parents slept (they both work late shifts). The grandmother reportedly left the house and went to the nearby residence of another family member after she put the baby down for a nap. He was later found inside a locked car parked in a neighbor's driveway. There was a child's stepstool next to the passenger door. Source

May 28: Lesli Selena Cuevas-Villagomez, 2 years old, of Wyoming, Mich.
Lesli was playing outside when her 14-year-old sister lost track of her. She was later found in a hot car. Her family thinks the girl managed to climb into the vehicle and could not get out. Source

June 4: Asante Arellano, 2 years old, of San Antonio, Tex.
Asante got into his family's parked car unnoticed; family members thought he was inside the home at around 3:00 PM and only realized he was missing at around 7 PM. Source

June 13: William Dylan Mahaffey, 4 years old, of Russellville, Ala.
William was playing hide-and-seek with neighborhood children when he apparently climbed in the vehicle. Source

June 16: Twins Allannah and Alliya Larry, 2 years old, of Portageville, Mo. 
The twins climbed into their grandmother's car outside of her apartment on their own while the grandmother was napping. The two girls had actually locked themselves inside a car before. Source

June 16: Alexia Ortiz, 11 months old, of Kingsville, Tex. 
Alexia's mother had just returned home from picking up her children when she mistakenly left the baby in the family car for 45 minutes. Source

June 18: Melody Bocanegra, 2 years old, of Longview, Tex.
Melody's dad accidentally left the girl in the backseat of the family car in the driveway for more than five hours. Her 13-year-old sibling discovered her lifeless body. Source

June 19: Holland Judy, 5 months old, of Lexington, Ky.
The infant's mother, a single mom with three other children, accidentally left the baby in the car in the driveway of the family's duplex. Source

June 19: James Marcus Jefferies, 3 years old, of Pinson, Tenn.
The boy's mother and her boyfriend searched for the child after the boyfriend came home from the store and saw that the door to the house was open and the child was missing. (The mother had been asleep inside the home while her boyfriend went to the store.) At about 4 PM, the child was found unresponsive in the car at his home. Source

June 21: Hunter Iles, 2 years old, of Hineston, Ala.
Hunter was found dead in the front passenger seat of his family's car after playing with other children outside his home. Source

June 27: Zipporah Johnson, 21 months old, of Phoenix, Ariz.
Zipporah's parents had gone to church with their six children and traveled in two vehicles, one of which was a minivan. The father accidentally forgot to bring Zipporah inside from the backseat of the minivan. Source

July 11: Anthony Michael Hickey, 18 months old, of Rockport, Tex.
The family was visiting the child's great-grandmother when Anthony went missing. He was later found unresponsive in the family SUV. Source

July 13: Jaden Carpenter, 3 years old, of Chandler, Ariz.
Jaden slipped out of the house and got into the car when his mom was studying. He was discovered dead less than thirty minutes later. Source

July 14 - Jahzel Pinon, 2 years old, of Albuquerque, N.Mex. 
Jahzel's mother accidentally left her behind in the car when she took her 4-year-old to an appointment. She said that she forgot the child was in the vehicle. Source

According to Janette Fennell, founder and president of Kids and Cars, a national nonprofit group that advocates for child safety, roughly 36 infants and children die annually in the U.S. due to being trapped in hot cars.

As mentioned above, TWELVE children have died in 2010 after playing in vehicles. It's imperative to keep car doors locked at all times -- and to keep keys out of the reach of children. Often, boys go into cars to push buttons and play with the wheel like they see their parents do, says Fennell. "A lot of times, they get unlucky and the doors are locked," she told AZ Central. "Or the heat overtakes them and they pass out."

Eleven kids so far in 2010 were forgotten in vehicles. Of these cases, four children were forgotten by their mothers, three by their fathers, one by both mother and father, two by family friends and one by a great-grandmother.

How could someone forget their child? "Everyone thinks these parents are bad or strung out on drugs, but parents who've lost their kids in these types of accidents include pediatricians, doctors, school principals, lawyers and NASA engineers," says Fennell. "For the most part, these are highly educated, extremely loving and doting parents."

Fennell says these accidents have little to do with how good a parent is, and everything to do with how a memory functions -- or doesn't function. "In the early '90s, these cases were rare," she says. "But then, in the mid-'90s, front-passenger airbags were installed in cars and there was a huge campaign to get kids to move to the backseat. An unintended consequence of this was kids dying of hyperthermia in cars -- because children were out of sight, out of mind."

In many of the cases, the forgotten children are under the age of 1 and are sitting in rear-facing car seats. Their parents are not sleeping much -- which comes into play. "And in an overwhelming majority of cases, there has been a change in routine," Fennell adds.

She says that the biggest mistake parents can make is thinking that this cannot happen to them. "That's what these parents probably thought, too," she says. 

Here, Fennell shares three ways to help prevent these deadly accidents:

1) Starting today, keep a teddy bear or stuffed animal in your child's car seat. Whenever your child is in his or her car seat, put the stuffed animal in the front passenger seat as a visual reminder that your child is in the back.

2) Keep your lunch bag, employee badge or purse in the backseat. That way, you'll always reach into your backseat or open your back door when you arrive at your destination.

3) Have an ironclad policy with your daycare provider that if your child does not show up, that person will call a provided list of contacts to confirm his or her whereabouts. "In so many cases, if the daycare provider would have called, tragedy could have been averted," says Fennell.

Kids and Cars is working hard to pass legislation that would require auto makers to install weight-recognition sensors in cars that would alert parents who've left their kids in the backseat. "We won't give up until it's passed, because it would save countless lives," Fennell concludes.

Our hearts go out to the families of the 23 children who've died.

What do you think of parents who've left kids in cars? Is it a tragic accident ... or the result of just plain neglect?