Southwest Airlines
Southwest Airlines planes are seen at LAX airport in Los Angeles, California, United States, Oct. 22, 2015. Reuters/Lucy Nicholson

A same-sex couple accused Southwest Airlines of discrimination after the carrier allegedly refused to let them board Saturday with their three children and 83-year-old grandmother during family boarding. Grant Morse and Sam Ballachino, who have been together 26 years and legally married for five, said an airline official told them the preboard was “only for family boarding.”

The Florida couple were flying from Buffalo, New York to Fort Lauderdale, Florida for the weekend with their children, a 5-year-old daughter and 3-year-old twin boys. Morse told WBBH-TV, a local NBC affiliate, that he’s a frequent flier with Southwest Airlines and has used priority boarding many times before.

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When Morse and his family attempted to board during the priority period, Morse claims he was approached by a representative who stopped them. “Excuse me, this is family boarding only,” she allegedly said, according to USA Today. “This is only for family boarding.”

“Well, we are a family and we're married, and these are our three kids,” Morse replied. “And that's our 83-year-old mother that is helping us.”

Morse maintains that after speaking with the agent, the children were allowed to board with one adult. Morse called the incident “very, very painful.”

“And I'm like, ‘I’m a father and he's a father. It is impossible for one person to push three strollers and handle twin boys at 3 and a girl at 5,’” Morse told USA Today.

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Southwest Airlines, for its part, maintains that the conversation “nothing to do with discrimination,” adding, “we welcomed these parents to board the aircraft with their children.” In a Wednesday statement provided to International Business Times, the airline said that an internal investigation “yielded consistent perspectives from several Employees and other Customers in the gate and onboard the aircraft that day paints a situation different than that which this Customer is sharing publicly.” The statement continued:

“We regret any feelings of a bad experience yet steadfastly support our Employees who were working the flight and enforcing our policies to protect the integrity of our unique open-seating.

Prior to the departure of Flight 5136 from Buffalo to Fort Lauderdale on May 20, we welcomed all families to board the aircraft during Family Boarding between the “A” and “B” boarding groups. Our Operations Agent (at the boarding door) informed two parents that another member of their group was ineligible to board under Family Boarding and asked that she board in her assigned boarding group. The two parents did not agree with our policy, and our Flight Crew worked to save seats together on the aircraft for the family as the conversation continued in the gate area. Our Family Boarding Policy is explained on Southwest.com and our Employees work hard to follow the policy to accommodate families traveling together while also maintaining boarding priorities for all of our Customers.”

The airline added that it “welcomes more than a hundred million customers each year,” and pointed to both its workforce and its “multi-cultural customer base” as evidence that it neither condones nor tolerates discrimination of any kind.

According to Southwest Airline’s family board policy on its website, “An adult traveling with a child six years old or younger may board during Family Boarding, which occurs after the “A” group has boarded and before the “B” group begins boarding.”