On Monday, John Hughes, her brother-in-law, John Hughes, spoke to Action News to share what the family is going through.
"This should be a joyous occasion, and everybody should be talking about how we're going to get together and exchange gifts, and now it's -- what are we going to do?"
Around midnight on December 8th, Rivera was driving north on 13th Avenue in Kings County.
The CHP says a Toyota 4Runner traveling west on Fargo Avenue at a high speed ran a stop sign and slammed into Rivera's SUV.
Investigators say the driver, Phillip Chavez Macias, had a blood alcohol level three times the legal limit.
He was taken to the hospital with significant injuries.
Rivera died at the scene.
"A mom is gone, a wife is gone, a sister, a daughter, a friend. Gone because of one person's careless choices," said Hughes.
On Monday morning, the 35-year-old suspect was arraigned over video from his hospital bed.
He pleaded not guilty to second-degree murder with aggravated circumstances for two prior DUI convictions, as well as other factors.
"Justice for us is seeing him behind bars where he can't hurt another family like he's hurt our family," said Hughes.
Her husband of nearly 20 years, local police officer Jon Rivera, shared a statement with Action News.
It reads in part, "Kellie's death has left a massive hole in our family. She loved deeply and without exception. As we mourn our loss, please take the time to hug your loved ones a little tighter."
In an additional statement, Rivera's family said:
"I'd like to thank the community for their outpouring of love, prayers and support."
The family is asking those to please respect their privacy.
Hughes is also urging everyone not to drink and drive so other children are not left without a parent because of a preventable tragedy.
"How do you tell a 4-year-old that can't happen, or how do you tell an 8-year-old who says, 'I know Santa has magic. I know he has magic, and he can bring my mommy back 'cause I don't want gifts; I just want my mommy back. How do you tell her Santa's magic doesn't work that way?"
This week, Kellie Rivera's family will continue one of her favorite holiday traditions, traveling to the Fresno Chaffee Zoo to see the lights at Christmas.
Chavez Macias is being treated at Kaweah Health. He faces the possibility of life in prison if convicted.
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