31-year-old Courtney Osegueda was hit while walking along MacArthur Boulevard in Oakland last week, according to her family.
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The car that hit her took off, leaving Courtney to die from her injuries.
ABC7's Dion Lim spoke with her sister, Kristen Osegueda, Saturday night.
She says the family can't come to terms with what kind of person would be so careless.
"It was one second of their life that ended someone else's life. And it's really hard to come to terms with that," Kristen said.
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Flowers and balloons now line the road where Courtney was killed.
She leaves behind an 8-year-old daughter. Kayleigh.
Her family is pleading for the driver to come forward, saying it's the only way they'll have some closure for their unbearable grief.
"We talked every day and I've been kind of just like stopping myself from looking at our text messages and, ya know, I feel like I kind of want to save that to look at so that I have something to look at later," Kristen said.
ABC7 News reached out to Oakland police for an update on the investigation and haven't heard back yet.
Meantime, family friends have set up a GoFundMe page to help Courtney's daughter.
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