Crime Boy, 5, Dies in Hot Car Outside Texas Elementary School, Teacher Charged with Negligent Homicide Temperatures reached 101 degrees in Mission on August 25, the day the boy died By Chris Harris Chris Harris Twitter Chris Harris has been a senior true crime reporter for PEOPLE since late 2015. An award-winning journalist who has worked for Rolling Stone and MTV News, Chris enjoys prog rock, cycling, Marvel movies, IPAs, and roller coasters. People Editorial Guidelines Published on September 16, 2022 11:17 AM Share Tweet Pin Email Diana Treviño-Montelongo. Photo: Hidalgo County Sheriff's Office A weeks-long investigation into the hot car death of a 5-year-old Texas boy has led to the arrest of a teacher in La Joya. Authorities say Diana Treviño-Montelongo is the aunt of the victim, who died on Aug. 25, reports the Progress Times. Treviño-Montelongo, 37, was charged Thursday with criminally negligent homicide. She posted $50,000 bond for her release. PEOPLE was unable to reach her by phone Friday. The child, who has not been named, was left inside a car that had been parked at Dr. Americo Paredes Elementary School in Mission, where Treviño-Montelongo is a teacher, according to KGBT. The La Joya Independent School District has placed Treviño-Montelongo on paid administrative leave. What to Know About Hot Car Deaths and How to Avoid Them The boy died from heat asphyxiation, medical examiners determined, according to The Monitor. Temperatures reached 101 degrees the day the boy died, according to the National Weather Service. Want to keep up with the latest crime coverage? Sign up for PEOPLE's free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases. The Monitor reports that Treviño-Montelongo was named the school's teacher of the year in April. Prevent Hot-Car Deaths: A Checklist for Parents Treviño-Montelongo spoke about the honor in a YouTube video. "My passion for education? Well I originally wanted to be a social worker, cause I always wanted to help kids and be able to be there for them," she explains in the video. "But then I was thinking about it, and I was like, that's gonna be kinda tough. I think being in a classroom, I can be there for them in a better way."