PEOPLE Explains: Was Southwest Wrong to Ask Mom of Biracial Baby to 'Prove' Child Was Hers?

Southwest apologized on Wednesday for asking the mother of a biracial child to prove the baby was hers before boarding a flight — but was the airline in the wrong? Not exactly, an expert says.

Passenger Lindsay Gottlieb detailed a troubling encounter with an employee of the airline on Twitter, writing, “I’m appalled that after approx 50 times flying with my 1 year old son, ticket counter personnel told me I had to ‘prove’ that he was my son, despite having his passport.”

The attendant reportedly told Gottleib, who is the University of California Berkeley women’s basketball coach, that it was because she and the baby had different last names. “My guess is because he has different skin color,” Gottlieb wrote. She also writes that the employee asked to see her son’s birth certificate and Facebook posts as proof.

Southwest has since issued an apology to the family. “We have reached out to Ms. Gottlieb directly to address her concerns and will utilize the situation as a coaching opportunity for our Employee. We apologize if our interaction made this family uncomfortable — that is never our intention,” the airline said in a statement, according to the Associated Press.

Twitter users sounded off, both in support of Gottleib and to defend the actions of the airline. One voice backing Southwest was model and TV personality Chrissy Teigen.

“Airlines have asked this of me, too, with my daughter,” tweeted Teigen, who shares Luna, 2, and Miles, 2 weeks, with husband John Legend. “Once I learned it’s a precaution for the very real threat of child trafficking, I stopped being exasperated with it. Now I’m kind of worried when they don’t ask.” She also notes that she now carries a “file folder of papers” when she travels with her kids.

Teigen is doing it right, according to Tracy Stewart, an air travel expert and editor at Airfare Watchdog.

Here’s what he says should have happened and why.

“Southwest policy does require parents to provide a birth certificate for children younger than two years. This helps the airline confirm the parentage, something that can’t be determined by checking a child’s passport alone,” says Stewart. “A birth certificate, and, in some cases, adoption papers, are typically all the proof the airline needs. If the child is traveling with someone other than a parent or legal guardian, the airline rep can ask for a letter of consent.”

Still, he allows, “it’s definitely unusual for an airline employee to ask a passenger to provide social media profiles, even as an additional means of identification. This is something that’s even off limits to TSA and Customs and Border Protection agents.”

Stewart points out that some of these rules vary by carrier and not all airlines ask for additional forms of ID when traveling domestically. For international travel, however, they require a passport for babies, just like they for would adult travelers.

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So what should the parent of a young child have with them when flying?

“Even if your airline requires a birth certificate, it wouldn’t hurt to bring along additional documentation such as a passport, immunization records, or, for older children and teens, school IDs, report cards, or a social security card,” says Stewart.

Still, uncomfortable encounters like Gottlieb’s are bound to happen.

“As travelers, we often trust airline employees to be more knowledgeable than us when it comes to company policy and federal regulations, but anyone who reads the news knows this isn’t always the reality,” he says. “Travelers are often left feeling powerless when things go wrong. Check individual airline requirements online before heading to the airport. And, if at any point you feel an airline employee oversteps their role, definitely report it to the airline after the fact.”