Mentone, Indiana (CBS News) -- In a tragedy that brought even first responders to tears, a 9-year-old girl and her twin 6-year-old brothers were killed Tuesday morning while crossing the street to their stopped school bus. Just before sunrise, a pickup truck hit the siblings and another boy who was seriously hurt. The driver, a 24-year-old woman, is charged with three counts of reckless homicide.
Elgin Ingle, the uncle of Alivia Stahl and Xzavier and Mason Ingle, described Alivia as a "mother hen" who was always watching out for her little brothers.
"It's horrible that this happened," Ingle said. "They were holding hands every day on the way to the bus stop including today…it looks like Alivia stepped in front of the car for the boys. It looks like Alivia seen what was happening, and she stepped up like a hero. I wish she could've saved her brothers, but she's still a hero."
Investigators are looking into whether school bus safety played a part in this horrific crash.
"Troopers and first responders don't do a lot of crying at scenes like this but today there were some tears shed," said Indiana State Police Sgt. Tony Slocum. "All evidence so far indicates the bus had its lights activated and had the stop arm extended."
It is illegal in all 50 states to pass a school bus when it is stopped with its lights flashing and stop arm extended. But by one estimate, more than 15 million Americans illegally passed by stopped school buses during the last school year – that's nearly 85,000 times each school day.
Cameras have caught just how dangerous that can be. In Austin, Texas, a car slammed into a child who had just gotten off the bus. He was able to walk away. One of the solutions explored is adding extended stop sign arms to the side of buses. It does not appear the bus in Indiana had that.
The driver is also charged with a misdemeanor for passing a stopped school bus and is free on $15,000 bond. The mother of the 11-year-old who was seriously hurt in the incident says he successfully made it through his first three surgeries, but he has a long recovery ahead.