Sarah Thomas thought she and her little sister Elizabeth had no secrets. Only two years apart in age, the girls also attended the same high school in Maury County, Tennessee.
So when 15-year-old Elizabeth frantically shook her big sister awake the morning of March 13, Sarah knew something was wrong.
“She said, ‘I’m going to be gone,’ ” Sarah, 17, recalls to PEOPLE in this week’s issue, on newsstands Friday. “She had a strange edge to her voice. She said, ‘I’m going to get back at 6 tonight. If I’m not back by 6, call the police and come find me.’ “
That was more than two weeks ago — and by the time authorities were contacted, Elizabeth had vanished.
Investigators suspect she was abducted by one of her teachers, 50-year-old Tad Cummins, whom her family has accused of “grooming” her.
Looking back, Sarah says there were warning signs of the disappearance, which has sparked an ongoing AMBER Alert.
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The weekend before Elizabeth was allegedly kidnapped, she told Sarah she couldn’t go to a party “if it was past Monday.”
In another instance, Sarah says, Elizabeth declared she had to break up with her well-liked boyfriend because she “wasn’t allowed to be with him anymore.”
Cummins was dealing with his own problems: He was suspended from teaching after he was accused of kissing Elizabeth on school property on Jan. 23, according to the Tennessee Bureau of Investigation.
A warrant has been issued for Cummins’ arrest on charges of aggravated kidnapping and sexual contact with a minor.
He was fired after he was identified as the suspect in Elizabeth’s disappearance, and prosecutors say the pair traded “romantic” messages via his school email.
On Monday, the Thomas family’s attorney revealed that Elizabeth may have tried to change her mind in the moments before going missing: Minutes before she was dropped off at the Shoney’s on March 13, she asked her friend to turn around and take her home.
But her friend had to go to work and didn’t listen.
How to Help
Authorities believe Cummins is likely keeping Elizabeth “off the grid” and they’ve urged the public to search their properties, local campgrounds, rural areas and parking garages.
Elizabeth was last placed in Alabama and was last seen wearing a flannel shirt and black leggings. She is 5 feet 5 inches inches tall and weighs 120 lbs., with blonde hair and hazel eyes.
Cummins was seen driving a Silver Nissan Rogue with Tennessee license plate 976ZPT, according to the TBI. He is 6 feet tall and weighs 200 lbs., with brown hair and eyes.
Anyone with information on Cummins or Elizabeth should call the TBI at 1-800-TBI-FIND.