Transcript for United Airlines forces 2-year-old from his paid seat

Items knocked right off the shelves. Tremors felt all the way in Spokane, Washington. The airline apologizing for forcing a toddler from his seat and forcing a mother to hold him even though she bought a ticket for him. She claims she was told the flight was full. They gave the seat to someone else. Here's ABC's linsey Davis. Reporter: United airlines is back in the headlines tonight, after Shirley Yamauchi says she was forced to hold her son, seen in these photos, on her lap for a 3 1/2-hour flight. The tickets were scanned without any incident. Reporter: She says she paid almost a thousand dollars each for two tickets for the flight from Houston to Boston, but that the airline made her give up her 27 month old son's seat for a standby passenger even after she told the flight attendant she paid for two seats. She came back and told me that the flight is full and she shrugg and that was the end of it. Reporter: The teacher says she "didn't want to cause a scene" like this one where a doctor was dragged off of a plane for refusing to give up his seat on an overbooked flight. And according to united's own manual only "Childn under the age of 2 are allowed to travel on an adult's lap." It was unfair and unsafe. If there was bad Tesh lens, he wasn't buckled in. Ms. Yamauchi's son. As a result, her son's seat appeared to be not checked in, and we released his seat to another customer. My son was in dangerous united tells us they are refundsing their tickets and providing compensation. Yamauchi says she is contacting it. There is an update on the

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