Canada's largest airline, Air Canada, has apologised after giving a 10-year-old boy's seat to someone else.
Cole Doyle and his family had planned a trip to Costa Rica but the first leg of the journey was overbooked.
The family travelled to two other airports and spent an extra C$1,000 (£590) to get a flight. The airline has now offered them compensation.
It comes after video of a man being dragged from a US flight brought booking practices to public attention.
Dr David Dao has said he will sue United Airlines after he lost two front teeth and his nose was broken when the airline called security officers in to help remove him from the plane.
He had refused to leave when the airline asked for volunteers to make way for staff members.
In response to the huge backlash the company faced on social media, United said it would allocate seats for staff at least an hour in advance, in future.
It also promised it would no longer ask law enforcement officers to remove passengers.
Separately in the UK, two passengers were asked to leave an Easyjet flight they had already boarded, and told the next flight to their destination was in four days. They decided not to reschedule, as they had booked non-refundable accommodation.
After the United incident, the Canadian government announced it would overhaul the rules to "ensure that passengers' rights are protected".
But well before that, Cole Doyle and his brother and parents were inconvenienced by an overbooking problem.
In March, the Doyle family tried to check in online to their flight to Montreal but could not assign a seat to Cole.
When they got to the airport at Charlottetown on Prince Edward Island, they were told there was no seat for him as the flight had been overbooked.
His mother, Shanna, asked whether an adult could give up their seat for Cole but was told that even if someone did so, it would be likely to go to another passenger and could not be guaranteed for the boy.
The family drove the two hours to Moncton in neighbouring New Brunswick, in the hope of getting on another flight.
"I'm crying in the back seat," Cole told the Canadian broadcaster CBC afterwards."Like how do I get to where I'm going? I don't know if I'm even going to make it with my family."
Once they got there, though, they found out the flight they wanted had been cancelled.
"I thought it was a joke," said Cole's father, Brett. "People are fed up. You shouldn't be able to sell something twice."
The family eventually made it to Montreal and caught a connecting flight to Costa Rica for their holiday, but have since complained to Air Canada and received an offer of a C$2,500 (£1,500) voucher, along with an apology.
An airline spokeswoman told the Canadian Press news agency: "We are currently following up to understand what went wrong and have apologised to Mr Doyle and his family as well as offered a very generous compensation to the family for their inconvenience."