Monique Munoz, 32, died after her Lexus was hit by a Lamborghini allegedly driven by a boy, 17, in Los Angeles last month.
Ms Munoz died while the boy was hospitalised with minor injuries.
Her stepdad Isaac Cardona claimed the driver was speeding up to 193km/h.
He added his stepdaughter “had a heart of gold”.
Teen's father apologises
The boy’s dad has been identified as local businessman James Khuri who has more than one million followers on Instagram.
On Wednesday, Mr Khuri issued an apology to the Munoz family.
"Knowing that this will never do justice for the family of Monique Munoz, I want to apologise to the Munoz family for the tragic loss of their daughter," Mr Khuri wrote.
"I realise none of my words or actions will be able to bring back your daughter. Still, I want to offer my support in any way you will allow me to. My family and I pray for the Munoz family."
Who is James Khuri?
According to The Jerusalem Post, Mr Khuri has made millions off manufacturing and distributing popular trading cards for Pokemon and Yu-Gi-Oh.
One photo on Instagram shows him with four Lamborghinis. None of them are the model his son crashed though.
Mr Khuri told Forbes he also sells “health, makeup, and tattoo products, as well as products from Hasbro and Mattel”.
His son is yet to be charged with an offence but could be charged with vehicular manslaughter, The LA Times reported.
Munoz family's frustration
Carol Cardona, Ms Munoz’s mum, told Fox News she has found the ordeal “very frustrating”.
“I believe he’s being protected given [the] status of his dad,” Ms Cardona told Fox News.
Ms Munoz’s sister Amber Nicole tweeted the boy is “hiding behind daddy’s money”.
“I lost an older sister, because a rich, spoiled, privileged individual wanted to race his fancy Lamborghini. He killed her,” she tweeted.
Mark Werksman, a lawyer for the teen, told Fox News the boy is still recovering after two weeks in hospital with a traumatic brain injury.
Mr Werksman claims his client was not racing at the time of the crash and the teen will appear in juvenile court next month.
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