For parents, it can be stressful enough to put your children on a plane on their own. And it only gets more irritating when you have to sort through each airline’s particular policy for unaccompanied minors to make sure your child will actually be able to fly without an adult — and how much it’s going to cost. But even then, the airlines can throw in a hitch that invalidates all your efforts.

Take the story of Consumerist reader Jennifer. She recently made plans to send her two sons — ages 11 and 17 — to fly from Oklahoma City to Philadelphia. After comparing the various airline’s policies for unaccompanied minors, she decided on U.S. Airways because the carrier allows children under the age of 14 to fly as an “accompanied minor” if they travel with someone who is at least 15 years old.

Even though this obviously meant that her two sons would be fine, Jennifer still called up the airline to verify that she understood the policy.

“I was assured this was no problem,” she tells Consumerist. “No problems occurred when I put in their names and birth dates and the tickets were allowed to be purchased.”

It wasn’t until after everything was purchased that she noticed the note on the ticket saying, “flight operated through United.”

But since she’d gotten verbal confirmation from U.S. Airways that all would be well and had been allowed to buy the tickets without problem or warning message, Jennifer didn’t think much about it.

Unfortunately, when she arrived at the airport to check in her kids, that’s when Jennifer was told that United doesn’t have an exception for young children traveling with an older teen, thus her 11-year-old was an unaccompanied minor. This meant a $99 fee for each flight.

She explained the situation to the United agent, who was able to remove the fee for the outbound flight but said Jennifer would need to contact the airline about the fee on the return trip.

“I spoke to 6 customer service agents (four with U.S. Airways, two with United) and not one of them would give me a reasonable answer as to why I was even allowed to purchase the tickets in the first place,” writes Jennifer. “I got every excuse from ‘well our computers don’t talk to each other’ (which is funny because the United ticket agent had no problem changing the flights to all United flights), to ‘I should have read the fine print.'”

Of course, argues Jennifer, she had already read the fine print — for U.S. Airways’ policies. It’s reasonable to assume that if U.S. Airways is going to allow you to book seats on United flights, it should at least mention that airline’s policies when you reserve the tickets.

“As of right now, all I want is a solid answer as to why I was even allowed to book the flights knowing that, according to the customer service agent I spoke with, all U.S. Airways flights out of Oklahoma City are handled through United,” she writes. “When I called U.S. Airways to inquire before I booked, why wasn’t I told ‘that they will be fine to travel except some cities our flights are handled by United and they have different travel rules’?”

We’ve never been able to understand why the major domestic carriers can’t just put their heads together and come up with a standard for policies like those regarding unaccompanied minors. There is almost no agreement on age thresholds, exceptions and associated fees, and no real rhyme or reason for the disparities. We’re reaching out to the airlines for some sort of explanation.

Luckily in this case, Jennifer was able to get at least half of the fee voided. But not everyone gets such a sympathetic agent at check-in, so there’s no telling how many parents are being hit with unexpected fees because the airlines just can’t get their act together.

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