The husband of a woman who died after being unable to return home on three different airlines for a kidney transplant is suing for $6 million.  

Her husband argues that the death was entirely preventable.

Bronx resident Vilma Soltesz and her husband voyaged to their vacation home in their native Hungary for a month. They traveled to Budapest from New York via Amsterdam, using the airline KLM Dutch Airlines. The 407-pound woman, who had only one leg, was able to board the flight with an airlift and then used a seatbelt extender once she was seated. Her husband's lawyer Holly Ostrov-Ronai said that the couple had no problem making it to Hungary. The airline even asked when Soltesz would be returning home so that they could make proper arrangements.

After the couple's vacation, they returned to the airport on October 15. Soltesz was able to board the flight, but the airplane's captain forced her to disembark due to a problem with the seat back, Ostrov-Ronai said.

"There was simply no legitimate reason in this instance for denying her boarding or forcing her to disembark," Ostrov-Ronai said to ABC News. "Their failure to make simple accommodations, that had been made prior, led to Vilma's death. This is not best efforts in any regard."

The couple waited at the airport for five hours while the airline tried to arrange accommodations for Vilma Soltesz. Finally, the couple was advised to drive to Prague, where a larger Delta airplane could hopefully fit her. However, once they arrived at the airport in Prague, the Solteszes were told that they only had a plastic wheelchair and no airlift, and thus were unable to transport her onto the plane.

Afterwards, the couple returned to Hungary before attempting to board a Lufthansa flight going to the United States. However, after boarding the flight, they were forced to disembark once again, because Ms. Soltesz was unable to properly fasten her seatbelt.

Lufthansa said that they worked with the fire brigade and technical experts to try to accommodate Ms. Soltesz, but nothing worked.

"After several time-consuming attempts it was decided that for the safety of this passenger and the over 140 fellow passengers, Lufthansa had to deny transportation of the passenger," the airline said in a statement. "In order to avoid further delays which would have resulted in missed connections and severe inconvenience for other customers on board, this decision was unavoidable."

The airline says that it reserved three seats for her, but the crew was unable to move Ms. Soltesz from her wheelchair to the seats after 30 minutes.

"Of course nobody said she was too fat to fly home," spokesman Nils Haupt said to Business Insider.

Ms. Soltesz died two days later, on October 24, after being unable to return home for diabetes and renal treatment.

Delta spokesman Russel Cason said that the airline offered their "sincere condolences" for Ms. Soltesz's passing.

Janos Soltesz, her husband, is described as heartbroken by his lawyer. "They passed these people around from airline to airline and treated them with no dignity whatsoever, simply because they didn't want to deal with the situation," Ostrov-Ronai stated. "The only thing that keeps him [Janos Soltesz] going day to day is that he wants justice for what was done to Vilma and to try to make sure this doesn't happen to anyone else in the future."

The United States' Department of Transportation is investigating Ms. Soltesz's death.