"12 years ago today was the last time I saw this beautiful smile, kissed his sweet face or felt his little arms wrap around my neck," she wrote. "I had no idea that morning with him would be the last time I heard his adorable laugh and sweet voice call me mommy and see his eyes lit up with life and wonder."
Losing her son was "like being plunged straight into hell," she wrote, and it's a pain that she won't ever get over.
"If the scars on my heart were visible, people would gasp every time they saw me," Miller wrote. "I'm scarred beyond belief. I've walked through hell and still carry a piece of it inside me."
The hardest part of losing her son, she wrote, is that his death could have been prevented — if only she was aware that his car seat wasn't the safest one for a child his age.
"Had I just known about the dangers of booster seats for toddlers, had somebody warned me, I would have put him in a 5-point harness car seat...and that simple difference would have changed everything. It would have saved his life," she wrote. "I would have had the past 12 years of memories with my beautiful boy, instead of 12 years of grief and pain. I wouldn't have to imagine what my son would be like now, I would be able to hug him and tell him I love him and watch him grow into a man. But I lost all of that because of ONE mistake."
Now, she wants to do everything she can to prevent another family from going through the same tragedy. As Miller wrote, car accidents are the most common cause of death for children under the age of 15. That has been true for decades, and is still true, according to a new report in the Journal of Pediatrics.
The researchers in this study found that many deaths of children in car accidents are partially caused by misuse of seat belts and other restraints.
While a car seat may seem simple enough to install, the type of seat a child uses and how they are strapped in can make a big difference. Booster seats, like the one Miller's son was using, shouldn't be used until a kid is either eight-years-old or has grown out of the height and weight requirements of their front-facing car seat, according to the Department of Motor Vehicles.
Yet, many parents aren't aware of the risks of using the wrong seat.
"We are not protecting our children from the single greatest threat to their lives! It's madness," Miller wrote. "And deaths by car accidents can, in many cases, be prevented by proper car seat usage! Why are we not talking about this?! Why are there no awareness campaigns?"
"Please, if you have young children or know someone with young children, research proper car seat usage and talk about it with everyone you know," she wrote. "Car seat safety is not a 'parenting choice', it's a matter of physics and facts."