Toddler forced to sit on mom's lap for three-and-a-half hour flight

HOUSTON, Texas -- United Airlines is again apologizing for an incident that happened on one of its flights.

This time a woman who paid for a ticket for her toddler was forced to hold him on her lap after the child's seat was given away to another passenger.

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Shirley Yamaguchi and her son were traveling from Hawaii to Boston. The problem happened when they had a stop here in Houston.

The airline said an employee inaccurately scanned the toddler's boarding pass causing his seat to be released to another customer.

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Yamaguchi had to sit with her son on her lap for the final three-and-a-half hour ride to Boston.

She took pictures of him in all different, contorted sleeping positions throughout the flight and eventually had to have him just stand between her knees.

United said it is working with employees so the same mistake won't happen again, and the airline refunded her ticket.

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