It is every parent’s worst nightmare — getting a phone call that your child has gone missing.

But that is exactly what Georgia mom Monica Gilliam, 39, says she experienced after she dropped off her 12-year-old daughter at an American Airlines gate inside Chattanooga Airport about a week ago.

Her daughter was flying solo down to Miami from the Chattanooga airport in Tennessee for a three-week visit with her father, Gilliam told Fox News Digital in a phone interview. 

Gilliam said she paid $150 dollars extra, in addition to the ticket price, to make sure her daughter would be escorted directly to her waiting father once the plane landed, under the airline's "unaccompanied minors" program. 

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Gilliam, a professional photographer and mom of four from Chickamauga, Ga., posted a TikTok video last Saturday sharing what happened next: "Almost an hour after her flight landed, I got a call from American Airlines. It was the manager in Miami — the American Airlines manager — and he says, ‘Your child is missing. We’ve shut down the terminal. We don’t know where she is.'"

Gilliam’s TikTok video (shown above) quickly went viral; as of publication time, it had amassed some 1.8 million views.

Mom and daughter arrived early at the airport to check the girl in with the airline as an unaccompanied minor.

Gilliam said the trip began smoothly enough. Her daughter was scheduled to depart on a 6 a.m. flight, so mom and daughter arrived early at the airport to check the girl in with the airline as an unaccompanied minor.

"They give you a lanyard for your child to wear [around her neck] and it's got all of the child’s information inside it — their boarding pass, which lets everybody know that they're not traveling with an adult," Gilliam said. 

Unaccompanied minor at airport

Monica Gilliam dropped her unaccompanied daughter (shown at left, in a photo blurred to protect her privacy) at the Chattanooga airport for a flight to Miami. At right, a busy airport scene. (Monica Gilliam; Future Publishing/Getty)

Her daughter had breakfast at the airport; then a flight attendant took the girl to the aircraft and "got her boarded first, which is what they're supposed to do with an unaccompanied minor," said Gilliam.

"I stayed until the plane took off," said Gilliam, "and then I left, not thinking that anything was going to go wrong." 

Two hours later, Gilliam said she received a call from her ex-husband, who said, "You're not going to believe what happened."

Gilliam said she was incredulous. "How do you lose an unaccompanied minor?"

Her phone then rang again — and it was not good news, according to Gilliam. 

It was an American Airlines manager, telling her that her child was missing. 

Gilliam said she was incredulous. "How do you lose an unaccompanied minor?" she relayed to Fox News Digital about the conversation. "How did you lose my child?"

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Fox News Digital reached out by both phone and email to American Airlines and received an emailed response from the corporate communications office.

"We take these matters very seriously and are looking into what occurred."

"American cares deeply about our young passengers and is committed to providing a safe and pleasant travel experience for them," the airline said in the statement. "We take these matters very seriously and are looking into what occurred. A member of our team has reached out to the customer to learn more about their experience." 

American Airlines states its policy in regard to the picking up of unaccompanied minors by a guardian once they arrive at their destination: "For a seamless pickup, don't forget your government-issued photo ID. You'll need to show it to get a security pass and meet the child at the gate [in the U.S.]."

The airline also states as part of its policy, "You also need to show it [the ID] before we release the child to you."

In addition, "We suggest arriving at least two hours before the child's scheduled arrival so you have enough time," American Airlines says in its policy about the guardian's pickup of a child flying alone.

Fox News Digital attempted to reach the child's father via the mother but was not successful. The flight reportedly arrived early in Miami — and as the father told "Inside Edition" this week, "She [the daughter] immediately started texting me because she had [arrived and needed] to go into the terminal." 

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Fox News Digital also reached out to the Chattanooga Airport for comment on the incident and asked for its best safety practices for children when traveling; a public relations representative declined to comment. Fox News Digital also reached out to Miami International Airport, which referred Fox News Digital back to American Airlines. 

Unaccompanied minor - monica gilliam

Monica Gilliam, pictured here, said her daughter was traveling unaccompanied to visit her father; the child arrived at Miami International Airport and was unsure where to go, the mother said.  (Monica Gilliam)

Gilliam said she imagines what might have transpired in regard to her daughter when she landed. "I think, knowing her, she's very soft-spoken. [So] when the person at the window seat got up, she's like, ‘OK, I’ve got to get up, too.’"

Gilliam said her daughter told her that once she deplaned, "they [the flight attendants] just waved at her instead of saying, ‘Hang on just a minute. I see an unaccompanied minor lanyard around her neck.’"

Gilliam said she and her daughter "do travel together as a family," and that her daughter knows that normally, after landing, they proceed to baggage claim. 

American Airlines' guidelines posted on the company's website state that unaccompanied minor service is mandatory for children ages 5-14 who are traveling alone, as is a mandatory gate escort and a guardian contact. 

Fox News Digital also reached out to the Transportation Security Administration (TSA) for comment. A spokesperson replied via email, "This is not a TSA issue. This was a ticketed passenger who went through security with a guardian. The matter at hand has to do with what happened when the flight landed in Miami."

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Gilliam shared that her daughter said later, "I didn't know what to do. So, I kept walking."

Gilliam said that she and her daughter "do travel together as a family," and that her daughter knows that normally, after landing, they proceed to the baggage claim. 

airport

A Georgia mom recently described a frightening experience for her daughter once her flight landed in Miami. The girl ultimately made it safely to her dad once she landed, but the mother is speaking out to help prepare other parents for what could go wrong in these scenarios. (AP)

"She was trying to get ahold of her dad," said Gilliam, meaning by cell phone. 

"He was in line for his gate pass when he got a text from her, and he said, ‘I'm just going to stand still and if you're comfortable reading the signs, I'm going to try to get you to me as quickly as possible.’ And so that's what they did."

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"And she did make it to him," continued Gilliam — confirming that indeed, the child safely reached her dad at the Miami airport.

Gilliam said she'd also like to warn other parents about the unexpected events that may take place when a child travels alone.

"But [up until then] she was walking around alone with this unaccompanied minor tag on her," said Gilliam about her daughter. 

She was basically "letting people know — in Miami, which is a major human trafficking hub — that she was alone and trying to find her way" by virtue of having the tag on her, said Gilliam. (Florida is among the top states in the nation for the most reported sex trafficking cases.)

Miami International Airport passengers

In this May 2015 file photo, travelers are seen at Miami International Airport.  (AP Photo/Alan Diaz, File)

Gilliam said what matters most is that her daughter is safe. But Gilliam said she'd like to warn other parents about the unexpected events that may take place when a child travels alone.

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"I was so grateful that she is safe," she said. "But this could have ended really, really badly."

She said that "other parents and kids" who are traveling this summer need "to be aware that this can happen." 

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Gilliam said she is hesitating now before putting her daughter on another flight by herself.

"It's been a really frightening experience," she said.