United Airlines' decision to give a toddler's seat to a standby passenger forced a mother and her two-year-old son to endure a three-and-a-half-hour flight together in just one seat.

Shirley Yamauchi, a Hawaii teacher, bought the ticket for $1,000 three months ago, but a United Airlines stewardess told her the seat was given to someone flying standby, reports Dailymail.com.

Yamauchi bought the tickets for a teachers' conference in Boston. She purchased a ticket for her son, Taizo - paying $1,000 for each ticket because children over the age of two are required to have their own seat.

On the other hand, the standby passenger paid just $75 for his ticket.

Yamauchi, who works as teacher at the Kapolei Middle School, was sitting on the plane in Houston when a flight attendant came to check if Taizo was present.

"I told him that I bought both of these tickets and he tells me that he got the ticket on standby. Then he proceeds to sit in the centre," she said.

Source: Khaleej Times