Hillarie Galazka performed one final heroic act to save the lives of her twin sons before dying in her car from injuries reportedly caused by an out-of-control driver.
Her five-year-old children have been recovering in hospital after being saved by their mum, 29, who reportedly threw herself in front of them to protect them after her car was rear-ended, Fox 2 reported.
The family were travelling towards their home in Lincoln Park, Detroit in the US state of Michigan, on Monday (local time) when a 25-year-old driver struck them from behind at 145km/ph, according to Ms Galazka's mum Jodie Kelley.
After fleeing the scene, the driver was later located at the hospital. He was found to be driving on a suspended licence, with five current suspensions and two local warrants as well as two prior convictions.
"I am devastated ... I cannot believe that this man wasn't in prison for his entire life for all of his warrants. I can't believe he was behind the wheel doing 90 miles per hour (144km/ph) in an SUV," Ms Kelley told the network.
The brothers recalled a heartbreaking detail about the accident shortly after being delivered to the hospital.
"The boys say they saw her open her eyes, and look at them and then she closed her eyes, and never opened them again. They remember that," their grandmother said.
"Her body saved them."
Ms Kelley said her daughter, who has been remembered a "good-hearted, strong, beautiful woman", was her best friend.
A GoFundMe fundraiser has been established to support Ms Galazka's family with funeral costs and the expense of raising her twins and eight-year-old son, who wasn't in the car at the time of the crash.
The crash is being investigated by Michigan State Police .
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