Evelyn Mae Boswell was last seen in December, but wasn't officially reported missing until weeks later
Evelyn Mae Boswell
Evelyn Mae Boswell
| Credit: Tennessee Bureau of Investigation

The mother of missing Tennessee toddler Evelyn Mae Boswell has given authorities “inaccurate” information during police questioning, Sullivan County Sheriff Jeff Cassidy said during a Friday press conference.

According to Cassidy, the mother, Megan “Maggie” Boswell, has been “cooperating” during interviews, “but some of the information she has given us hasn’t really been accurate.”

He adds, “Surveillance camera footage, witness testimony — a lot of her story hasn’t been accurate.”

The 15-month-old girl was last seen sometime in December, according to authorities — but she was officially reported missing only on Tuesday.

During the press conference, Cassidy expressed doubt about when she was last seen. While Boswell says that she last saw the toddler on December 26, a babysitter says that she saw Evelyn around December 10th.

“I’m not going to go with what the mother said, because some of the stories are conflicting and inaccurate,” Cassidy said.

Boswell did not respond to PEOPLE’s request for comment.

Authorities first learned that Evelyn was missing after hearing from relatives who stated they had not seen the toddler since the holidays. The child’s mother did not report her missing. Instead, her grandfather did.

Evelyn Mae Boswell
Evelyn Mae Boswell
| Credit: Tennessee Bureau of Investigation

A statewide AMBER Alert has been issued for the girl.

The Sullivan County Sheriff’s office has enlisted the help of the FBI and the Tennessee Bureau of Investigation. The Tennessee Department of Children’s Services has also launched an investigation.

Authorities are not disclosing further details on their investigation — or disclosing why it took so long for the toddler to be reported missing.

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The toddler’s father, Ethan Perry, is active duty in the U.S. military, and is stationed in Louisiana.

According to her AMBER Alert, Evelyn is 2 feet tall and weighs 28 lbs. She has blonde hair and blue eyes. She was last seen wearing a pink tracksuit, pink shoes, and a pink bow.

Officials now say in the AMBER alert that they have information indicating that people traveling in a gray 2007 BMW with Tennessee plate 3M96W9 and front-end damage might have information in the disappearance of the toddler.

Anyone who has information about Evelyn’s whereabouts is asked to call the Sullivan County Sheriff’s Office at 423-279-7330 or the TBI at 1-800-TBI-FIND.