Brother of Teen Allegedly Kidnapped By Teacher: 'I Do Believe He Has Some Control Over Her'

The search has intensified for Elizabeth Thomas and Tad Cummins.

The brother of the missing teen who vanished with her 50-year-old teacher is speaking out.

Read: Girl, 15, Allegedly Kidnapped By Her Teacher Shared Instagram Post: 'Every Beauty Needs Her Beast'

On the morning of her disappearance with teacher Tad Cummins, Beth Thomas posted a troubling remark on Instagram that featured Belle and the Beast, from "Beauty and the Beast," that read: “Every beauty needs her beast to protect her from everything but him.”

Her older brother, James, told Inside Edition his 15-year-old sister is a big fan of Disney princess films.

“She has always been into Disney princesses and "Beauty and the Beast" just came out,” he said. “I do believe he has some control over her.

Prior to the pair's disappearance, another student at the school outside Nashville reported walking in on the two kissing, but it was another week before the school authorities suspended the teacher.

On Monday afternoon, the Tennessee Bureu of Investigation released the last known photo of Thomas, with information on how to help in her search.

NEW PICTURE: Here's the last known photograph of Elizabeth Thomas prior to her alleged kidnapping. Spot her? 1-800-TBI-FIND! #TNAMBERAlert pic.twitter.com/5hInjYHU5d

— TBI (@TBInvestigation) March 20, 2017

The Tennessee Bureau of Investigation have issued an Amber Alert for the missing teen and have posted new images of Cummins and Thomas inside a local WalMart days before the kidnapping. 

VIDEO: Here's surveillance of AMBER Alert suspect Tad Cummins, days before disappearing with Elizabeth Thomas. https://t.co/j1fuc5VJWH

— TBI (@TBInvestigation) March 20, 2017

MORE VIDEO: Here's a second clip of AMBER Alert suspect Tad Cummins. https://t.co/rnUJWNdx8l

— TBI (@TBInvestigation) March 20, 2017

Surveillance video allegedly shows Cummins filling up his silver SUV at a gas station moments before meeting the student at a nearby diner in Columbia. They drove south to Decatur, Alabama, which is 70 miles away but since then the trail has gone cold.

Police believe they may be headed for the Florida Panhandle. Cummins has at least $4,500 in cash after taking out a loan on his car. He also allegedly has two handguns.

Read: Wife Pleads For Husband, 50, To Return 15-Year-Old He Allegedly Kidnapped As Search Continues

An attorney for the girl's family says that, despite appearances, Beth Thomas may not have willingly gone with the health sciences teacher.

The Tennessee Bureau of Investigation said Cummins was driving a silver Nissan Rogue with Tennessee tag 976-ZPT. They have also released a series of images on Twitter, urging anyone with information on their whereabouts to contact them.

Your RT may just get this information in front of the one person who needs to see it. Help us spread this across the country! Thanks! pic.twitter.com/c5jI8ER816

— TBI (@TBInvestigation) March 17, 2017

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