The two were seated on the flight when Yamauchi said a flight attendant came to check to see if Taizo was in his seat.
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A man flying standby boarded the flight and indicated that his ticket has the same seat as Taizo: 24 A. According to KITV, the man paid $75 for his standby listing.
“It was very shocking. I was confused. I told him, I bought both of these seats. The flight attendant came by, shrugs and says ‘flight’s full’,” Yamauchi told KITV.
“I had to move my son onto my lap. He's 25 pounds. He's half my height. I was very uncomfortable. My hand, my left arm was smashed up against the wall. I lost feeling in my legs and left arm,” she said.
According to the Federal Aviation Administration, parent's arms "aren't capable of holding (a) child securely, especially during unexpected turbulence."
“The Federal Aviation Administration (FAA) strongly urges you to secure your child in (child restraint systems) or device for the duration of your flight. It's the smart and right thing to do so that everyone in your family arrives safely at your destination.”
Yamauchi said she wanted to speak up, but past incidents she saw on the news about the airline and passengers made her hesitant.
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“I started remembering all those incidents with United on the news -- the violence, teeth getting knocked out. I'm Asian,” she told KHNL. “I'm scared and I felt uncomfortable. I didn't want those things to happen to me.”
“What happened to my son was unsafe, uncomfortable and unfair," Yamauchi told KITV.
According to KHNL, United issued an apology five days after the flight.
"On a recent flight from Houston to Boston, we inaccurately scanned the boarding pass of Ms. Yamauchi's son. As a result, her son's seat appeared to be not 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 refunding her son's ticket and providing a travel voucher. We are also working with our gate staff to prevent this from happening again."