United Airlines forces mother to hold toddler during flight after selling his seat

United Airlines has apologized after it sold a two-year-old boy's seat during a layover on Flight 2047 from Hawaii to Boston, forcing his mother to hold him in her lap for the rest of the journey.

Shirley Yamauchi, 42, and her son, Taizo, were ready to begin the last leg of an 18-hour trip after a layover in Houston, Texas, when a male standby passenger boarded the aircraft with a ticket showing 24A, the same seat number as the toddler.

"It was very shocking. I was confused. I told him, I bought both of these seats. The flight attendant came by, shrugs and says 'flights full,'" Yamauchi told KITV.

Yamauchi says she was too afraid to cause a scene over the seat, remembering how Dr. David Dao was dragged off a United Airlines flight in April for disagreeing with a flight attendant's orders.

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"I'm scared. I'm worried. I'm traveling with an infant," she told KITV. "I didn't want to get hurt. I didn't want either of us to get hurt."

Yamauchi ultimately picked up her young son and endured the child's weight for the duration of the three-hour flight.

"He's 25 pounds. He's half my height," Yamauchi told KHNL. "I was very uncomfortable. My hand, my left arm was smashed up against the wall. I lost feeling in my legs and left arm."

Having purchased both her own seat and her son's seat for $969 each, Yamauchi said she was extremely confused over the double-booking -- especially considering that, according to United's own policy, children age two or older must have their own seat.

To make matters even worse, the man who took Yamauchi son's seat paid just $75, a fraction of the original ticket price.

United Airlines issued an apology days after the flight, admitting that the mishap was caused by human error.

"On a recent flight from Houston to Boston, we inaccurately scanned the boarding pass of Ms. Yamauchi's son," the airline said in a statement.

"As a result, her son's seat appeared to not be checked in, and staff released his seat to another customer and Ms. Yamauchi held her son for the flight. We deeply apologize to Ms. Yamauchi and her son for this experience. We are providing compensation as a goodwill gesture. We are also working with our employees to prevent this from ever happening again."

United also reportedly refunded Yamauchi for the price of both of her tickets and provided her with additional compensation.