The parents of a 10-year-old girl have accused United Airlines of losing their daughter and not being concerned about it.

On his blog, Stanford professor and author Robert Sutton (who also contributes to The Huffington Post), relays the story of two friends whose daughter was seemingly forgotten by the airline.

Annie and Perry Klebahn's daughter, Phoebe, was flying alone from San Francisco to Traverse City, Mich. via Chicago on her way to camp in late June. However, according to the pair, no United staff showed up to help Phoebe make her connection in Chicago, so she missed her flight. According the the Klebahns' letter to United, which is available in Sutton's post, the couple only knew their daughter did not make it when her summer camp in Michigan called to say she hadn't arrived.

According to the letter, the family was shocked to find out that not only is there a third-party unaccompanied minor service that escorts the children, but its representative had simply forgotten to show up for Phoebe. It took roughly an hour to locate the girl after it was discovered she was "missing." Apparently when the flight landed, she asked the flight attendants for help, but they told her they were busy and she needed to wait. She also asked thrice for access to a phone to call her parents, but was allegedly also told to wait.

Phoebe was placed on a flight to Traverse City four hours later. However, her bags didn't fly with her. In the letter her parents describe the three-day process involved in finally getting the girl's possessions to her.

"We estimate that we spent around 18 hours collectively on the phones, on hold, trying to track down Phoebe, her bags and our peace of mind," the parents wrote in the letter. Phoebe “never wants to fly United again."

In a statement to HuffPost Travel, United Airlines said:

We reached out directly to the Klebahns to apologize and we are reviewing this matter. What the Klebahns describe is not the service we aim to deliver to our customers. We are redepositing the miles used to purchase the ticket back into Mr. Klebahn’s account in addition to refunding the unaccompanied minor charge. We certainly appreciate their business and would like the opportunity to provide them a better travel experience in the future.

United isn't the only airline to get flak for issues involving unaccompanied minors. In 2010, Delta blamed a paperwork "swap" for sending two children to the wrong cities -- a boy ended up in Cleveland instead of Boston while a girl was sent to Boston instead of Cleveland. In that case, Delta apologized and sent the children to their final destinations at no cost, also issuing full refunds for their tickets and offering credits for future travel. In January of this year, a mother accused Southwest Airlines of negligence for leaving her napping 15-year-old son on a St. Louis-bound plane after the flight landed in his final destination of Tulsa.

Also curious is the case of the three kids who flew alone on a Southwest flight to Nashville in 2010, paying with babysitting money, while the airline asked no questions. And, there was the instance in July when an 11-year-old boy flew alone from Manchester, England to Rome on a Jet2 flight sans passport or boarding pass.

Virgin Australia's unaccompanied minor policy came under fire recently, with the airline pledging to review its protocol after the public outcry against the practice of not allowing men to sit next to unaccompanied children.

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