This story has been updated to include comment from United Airlines, received after publication.

Have you ever been to Denver? 

It's beautiful. One of my favorite cities in America.

As nice as it is however, I don't think I'd want to fly there by mistake.

Especially if I was intending to fly somewhere else--and even more especially, say, if my whole reason for flying was to be with a family member who was facing a medical issue. 

Unfortunately, that's exactly what happened to a United Airlines passenger this week.

A blind, 80-year-old passenger, in fact who didn't speak English--and whose family had requested special assistance from United Airlines, apparently.

Maria Larios was coming from El Salvador, intending to fly to Raleigh, N.C. in order to be with her daughter, who was due to undergo brain surgery.

Her first leg of the journey went fine; she landed in Houston (also lovely, at least as far as airports go), and looked for her connection.

Somehow, she boarded the wrong flight Tuesday evening, and headed toward the Rockies instead of the Research Triangle.

Her family said they figured out afterward that she'd actually had her boarding pass switched with someone else. So, it would appear United might have have actually sent another passenger who had intended to go to Denver, instead to Raleigh. 

It all sounds like the plot to a screwball comedy. But the family said they weren't laughing--not so much because the mixup happened, but because of United's reaction afterward. 

"She cannot read or write even in her own language. She can't speak English at all. So when you hand her a boarding pass, she's trusting that it's the right boarding pass," the woman's daughter-in-law told WRAL television.

"They were like, 'Oh yeah. We made a mistake, and she was given the wrong boarding pass and so she's in Denver. But it's not a big deal. We've already got her on a flight to Raleigh, and we gave her a meal voucher,'" she added. ""You lost a person, and the whole time they were treating me like they lost my luggage."

To be fair, given the sheer number of flights and passengers on United each day--148 million passengers a year, on 4,500 daily departures-- it's surprising this kind of thing doesn't happen more often. 

And, as View From the Wing's Gary Leff points out, United did settle an eerily similar case last year (a non-English speaking passenger in in Newark was sent to San Francisco, when she had a ticket instead for Paris, France).

"We deeply apologize to Ms. Larios and to her family for this experience," United said in a statement. "When she arrived in Denver, she was placed on the next flight to Raleigh and we issued a refund and a travel certificate.  Our customer care team is in contact with her family to ensure we make this right. We are also investigating this incident internally to better understand what happened so that we can prevent this from happening again."