Avonda Fox wonders what it was like for her 4-year-old son, Jacob, when he was accidentally left inside that sweltering Pleasant Grove day-care van on that blistering July day.
What was he thinking? Was he crying out for me?
For Fox, the pain is still deep three years after Jacob died of heatstroke after he was found on that day of triple-digit heat.
But she's taken a parent's horror and used that pain to try to help other families - and prevent other children from dying after being left behind in hot vehicles.
Fox helped advocate for a new state law that will require day-care workers involved in transporting children to complete two hours of transportation safety training each year.
"Jacob's Law" goes into effect in September.
"I wanted to try to save another life," Fox said. "It happens too often in Texas. This is reoccurring. It's so preventable.
"It just shouldn't happen."
On average, 37 children die each year across the country from vehicle-related hyperthermia whether left behind by day-care workers or parents, according to data compiled by Jan Null, a professor at San Francisco State University. There were nine deaths in Texas last year.
State Sen. Florence Shapiro, R-Plano, authored the bill after Fox met with her and shared her story. Shapiro said she has been outraged when she hears about Jacob and other children left in vehicles.
Texas doesn't require transportation safety training for day-care workers. Shapiro said her statehouse colleagues quickly jumped on board to push for the new law.
"We recognized this was a problem throughout the state of Texas, and we quickly brought it to the forefront that there must be change," Shapiro said. "We have a responsibility as adults to never let that happen, and the continuation of this problem is what was so appalling."
Last week, at Shiloh Terrace Baptist Church in Dallas, Fox stood in front of a room of about 100 people and shared her story.
"When accidents like these happen, it doesn't just affect the family who has lost the child," she said. "It affects the community. Employees lose jobs. The center shuts down. People need counseling."
Fox has teamed up with a local nonprofit agency, ChildCareGroup, to spread the word to area facilities about the new state requirements.
ChildCareGroup has developed a training manual and is distributing stickers, signs and keychains that say "Search our seats" - visual reminders for day-care employees to think about transportation safety.
But what resonates the most with day-care workers is a training video that features Jacob's story, as well as an interview with Amber Adams, the emergency responder who tried to help him.
"We get them by the heart so it sticks in their head," said Rhonda Rakow, customer support manager with ChildCareGroup.
In the video, Adams recalls leaving the emergency room and seeing Fox search for her son.
"She kept going, 'Where's my baby, where's my baby?' " Adams says. "I said, 'I think you might want to sit down.' ...
"She fell to the ground. And I went to the ground with her and I said, 'I'm sorry; I'm really sorry. I wish there was something I could have done.' "
Day-care operators statewide plan to conduct training at their facilities. A manual provided by ChildCareGroup addresses various topics, including the importance of having first-aid kits available and doing daily vehicle inspections and ways to account for children during trips.
Everyone, it seemed, loved Jacob, who was outgoing, enjoyed swimming and was just beginning to read.
He was left in the van on July 20, 2006. Day-care owner Blynithia Washington then ordered employees to take his body to a nearby park and not to call 911.
The day care was shut down. In 2007, Washington was sentenced to two years in prison.
"Some days I'm happy, some days I'm sad, and a lot of days I'm angry," Fox said. "After three years, I'm angry that this has happened to me. My son lost his brother. I lost a son. My mother lost her grandson."
Fox didn't have enough money to pay for her son's funeral, but donations helped cover expenses.
Not wanting other families in the same situation to have to worry about money as they grieved, Fox established the Jacob Fox Foundation, which helps pay for funeral costs.
Getting involved in Jacob's Law and the foundation has eased the sorrow a bit.
"When I speak to people, I channel that pain," said Fox, who works as a legal assistant. "The thing that keeps me going ... is that this can save a child."
Day-care providers at last week's presentation say they already have safeguards in place. But the presentation drove home the message.
Mae Oputa, director of Play N' Learn Christian Academy in Dallas, said her staff will find the "Search our seats" visual reminders helpful.
"In the hustle and bustle of day care - it's a fast-paced business - seeing something triggers in your mind that this is something you need to do because it may save someone's life," Oputa said.
Keeping track of every child may seem like common sense, but additional training is always helpful, said Vicki Rance, owner and director of It's a Child's World Day School in Irving.
"We want the best for them," she said. "We want them safe."