A Sacramento mother and her 8-month-old daughter have been missing for over 10 days

Authorities in central California are searching for a mother and her 8-month-old daughter, who haven’t been seen in almost two weeks since departing Fresno to return to their home near Sacramento.

Whisper Owen, 36, and her infant daughter Sandra McCarty were last seen on July 15, according to the Fresno County Sheriff’s Office.

“The not knowing, it’s brought me to a point where I’m — it’s a cross between anger and numb,” Owen’s mother, Vicki Torres, told CNN affiliate KCRA. “I’m terrified. I’m just terrified.”

The pair left Fresno, where KCRA reports they were visiting family, around 5 p.m. on the 15th, according to the sheriff’s office.

A traffic camera last captured their vehicle, a silver 2006 Chevrolet Trailblazer, shortly after 8 p.m. in Atwater, around 66 miles north of Fresno, says the sheriff’s office.

Since then, neither has been seen – and no information has been uncovered to explain their disappearance, according to the sheriff’s office.

“They were supposed to be heading home to Elk Grove (Sacramento County) where family members were expecting them,” said the sheriff’s office in a post on Facebook. Elk Grove is around 158 miles north of Fresno.

On July 19, four days after departing Fresno, Owen’s partner contacted her family to ask if she was there, according to CNN affiliate KFSN. Her brother, Richard Owen, told the affiliate he had informed her partner that Whisper had left on Tuesday night — then Richard reported them missing to law enforcement.

Torres, Owen’s mother, told KCRA the two had a “wonderful visit” in Fresno, where they attended a doctor’s appointment for the baby.

“The only thing she had to do was stop and get a can of formula because she was on her last bottle,” Torres told KCRA.

Owen “didn’t run away,” her mother said. She has a “good home life” and three other children, Torres told KCRA.

Torres told CNN affiliate KFSN her daughter doesn’t have a working phone so she typically only speaks with her every few days.

Family members are contributing to the desperate search for the pair, driving up and down the highway, according to KFSN.

CNN has reached out to the Fresno County Sheriff’s Office, the Fresno Police Department, and the Sacramento Police Department for more information.

CNN’s Lily Hautau and Jillian Sykes contributed to this report.

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