BOISE -- Brock Dewyar and his girlfriend Brie Nicolee knew they had precious little time to act.
She had a heartbeat, and as I started pushing on it, it started getting a little bit faster, Dewyar said, describing his efforts to revive a fatally-injured teenage girl.
The couple had just left their Boise home on Easter Sunday. They were among the first to respond to a deadly crash near a crosswalk on Ustick Road and Jullion Street.
At first it looked like a car wreck ... Dewyar said. Then I noticed the little girl laying on the road.
Police say 13-year-old Olivia Schnacker was riding her bicycle with two siblings when she was struck by the driver of a passenger car just befor 6:30 p.m.
Dewyar and Nicolee immediately pulled over when they saw the crash. They joined other witnesses who were already trying to help the girl.
Dewyar says he stepped in to perform CPR on the girl until paramedics arrived. He says the teen was laying face down in the road and struggling to breathe.
I just did what I had to do, Dewyar said.
Meanwhile, his girlfriend helped calm the hysterical woman who was driving the car.
I think she was more in shock, and she was just saying 'I'm going to go to jail. I couldn't see. The sun was in my eyes; I couldn't see,' Nicolee said.
Schnacker died of her injuries two days later at Saint Alphonsus Regional Medical Center.
Dewyar and Nicolee say the teen's broken body was found about 20 to 25 feet from the crosswalk.
Witness Jason Maestas says he believes the warning lights in the crosswalk had been activated when she was struck.
Maestas says he watched the car hit the girl while behind the wheel of his own vehicle, and immediately jumped out of his car to give the girl first aid.
He says his wife called 911, and dispatchers began giving witnesses on the scene instructions, including how to roll the girl onto her back, along with how to begin giving rescue breaths.
There was no braking whatsoever, Maestas said of the crash, adding that low visibility could have been a major factor in what happened.
That sun was setting ... That sun played a big role in that accident, Maestas said.
Police continue to investigate the deadly crash, but have turned down requests for comment. They have not identified or said if they'll charge the driver.
In the meantime, Brock Dewyar and Brie Nicolee have been following the story on social media.
They say their hearts go out to the parents of the dead teen.
It feels like you knew them, and you want to do more to help them, because it was very tragic, and I couldn't imagine, Nicolee said.
We're told 13-year-old Olivia Schnacker was student at Lowell-Scott Middle School in Meridian. The district says a crisis team is available for other students to grieve.
The family has established the Olivia Schnacker Memorial Fund at the Wells Fargo Bank.