COLUMBIA, Tenn. (WKRN) – One of Elizabeth Thomas’s older sisters spoke with WKRN Tuesday. She believes Elizabeth made the choice to run away.

“She’s a smart girl and I don’t believe she’d do something like this unless there was a motive behind it,” Brandy Landauer said. “Happy kids don’t run away from home, and if she was unhappy, that could’ve been the reason why she left.”

Landauer is Elizabeth’s older sister by four years. She says she and Elizabeth used to play guitar together and practice for church choir.

“She was a little spitfire,” Landauer said. “Elizabeth was fun to be around, she likes to joke, she was a great singer – I loved to hear her voice.”See also: TBI: AMBER Alert suspect researched teen marriage before disappearing

She says she, her sister, and their eight brothers and sisters had a good childhood.

Landauer says up until November 2015, she and her siblings were home-schooled, but they played sports and went to church three to four days a week.

In November 2015, their mother, Kimberly Thomas, was charged with child abuse. She moved out of the home.

Landauer was not far behind. She married her boyfriend, they moved into their own home, and they had a baby.

The 19-year-old older sister defends her mother and says there must be a reason why Elizabeth was running away.

Related: School documents show relationship between teacher suspect, missing teen Elizabeth Thomas

Now, she just wants her home.

“I just wish that she would come home because what she’s done can be forgiven. It already has,” Landauer said through tears. “And if she would just come home everyone would just accept her back as if nothing ever happened.”

Landauer worries that Tad Cummins will get desperate and hurt Elizabeth. She prays that’s not the case.

Neither of them have been seen or heard from since Monday, March 13. The TBI has said they’ve received hundreds of tips but none have given any credible leads in the case.

Cummins has been charged with Elizbaeth’s kidnapping in the case and also faces one count of sexual contact with a minor out of Maury County. He’s accused of kissing her at school.MORE: Maury County Schools releases timeline of investigation into Tad Cummins

Thomas is a 15-year-old white female, with hazel eyes, stands 5 feet tall and weighs 120 pounds. She was last seen wearing a flannel shirt and black leggings.

Cummins is a white male, who stands 6 feet tall, weighs approximately 200 pounds, and has brown hair and eyes.

He is believed to be armed with two handguns and driving a silver Nissan Rogue with Tennessee tag 976-ZPT.

On Friday, the TBI added Cummins to the state’s ‘Top 10 Most Wanted’ list. There is a $1,000 reward for information leading to his capture.

The TBI would urge the public to remain vigilant and report any information that may prove beneficial in the ongoing search to 1-800-TBI-FIND. If you spot the vehicle and can verify the license plate to be TN 976-ZPT, call 911 immediately.Click here to read more stories connected to this case.