Chilling final moments of California teen Alison Chao before she vanished riding bike to aunt's home

Friends and family of a 15-year-old girl, last seen a week ago riding her bike to a relative's house , are appealing to the southern California community for help in locating her.

Alison Jillian Chao, from Monterey Park, vanished last Tuesday as she left her father's residence on North Ynez Avenue at around 5.30pm, according to the Monterey Park Police Department. Surveillance footage last captured her at approximately 6.23pm on Collis Avenue in the El Sereno area of Los Angeles, where she was cycling her mountain bike to her aunt's home in San Gabriel.

The teenager never made it to the house, which is less than three and a half miles from Monterey Park. Alison is described by police as an Asian girl, 5 feet 2 inches tall, and weighing about 96 pounds, reports the Express US .

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She has black hair and brown eyes, and was last seen in a purple t-shirt, black shorts, and dark shoes. At the time of her disappearance, Alison was riding a blue mountain bike and carrying a black backpack.

Annie Chao, Alison's mother, described her daughter as "bubbly, upbeat and full of energy," according to KNBC . "She took her bike from her dad's house and rode down the driveway, headed towards her aunt's house in San Gabriel and never made it there," Alison's mother told the outlet.

"It was really hard to comprehend. You know, I don't think your mind can understand what's happening in that moment. I just, it's been a lot of sleepless nights," she continued.

The search for Alison is still very much active, with her loved ones plastering missing posters throughout Monterey Park, clinging to the hope that someone will spot her. "MPPD detectives, in cooperation with our local, county, state and federal partner agencies have been investigating this case continuously since Alison was reported missing," stated the Monterey Park Police Department.

"We continue to work with the Chao family and are canvassing neighborhoods in the area, reviewing surveillance video footage and interviewing possible witnesses." Alison, a top student gearing up for her junior year at Mark Keppel High School, seemingly vanished without a trace, not reaching out or updating her social media, reports KTLA 5.

"The more time that goes on, the scarier it gets," Alison's mother expressed to the news channel. "I'm afraid the public will lose interest, and it will be harder to find her. There's less evidence."

"I haven't slept in days, and it's just every parent's worst nightmare," lamented Alison's mother. The Monterey Park Police Department is urging anyone with information about Alison's location to get in touch with their Investigations Bureau at 626-573-1311.