Sarah Blackwood, member of the popular Canadian band Walk Off The Earth, says she was humiliated when she was kicked off a United Airlines flight over the behaviour of her toddler son, who the airline said was causing "safety concerns."

The singer, who is currently seven-months pregnant and on tour with the band, told she was kicked off United Airlines Flight 6223 from San Francisco to Vancouver on Wednesday because her 23-month-old son was being "fussy." The flight was operated by United's regional partner, SkyWest Airlines.

Blackwood said during the first leg of the journey, her son, Giorgio, was upset.

But it was during the second leg of the flight from San Francisco to Vancouver that she was warned by a flight attendant before takeoff that if she couldn't "control" her child, the pilot would be turning the plane around.

"I had to hold him, he was being very squirmy and was crying very loud," she said.

She said her son was sitting in her lap, as she hadn’t purchased a ticket for her child since he was under two years of age. Passengers are only required to purchase a ticket for their children if they’re two or older.

"I looked at her and said 'I'm doing what I can here, I'm holding him. This is what I'm supposed to do,'" Blackwood told in a phone interview from Vancouver.

As another flight attendant came up to her and started to speak with her, Blackwood said she started to get emotional.

"My eyes were welling up, I was so embarrassed," she said, adding that the man next to her was assuring her that it was OK, and that he had three children of his own.

Blackwood said that as the plane was taxiing, it suddenly came to a stop, turned around and headed back to the airport. She said the captain told the passengers that the plane needed to refuel.

But when the plane reached the airport, a different flight attendant came up to Blackwood and asked her and her son to leave. By this point, she said her son had fallen asleep on her lap.

When the singer asked why she was being forced off the flight, she was told it was because the flight attendants felt "unsafe" because her son was causing some kind of "threat" to the plane.

She said she felt humiliated as she was escorted off the aircraft, along with her nanny.

"It felt like it was in slow motion. I was in tears, it was so embarrassing. It was awful," she said.

In a statement to, SkyWest said the flight crew made the "difficult decision" to remove Blackwood and her son from the flight based on "safety concerns."

"Despite numerous requests, the child was not seated, as required by federal regulation to ensure passenger safety, and was repeatedly in the aisle of the aircraft before departure and during taxi," the statement said.

"While our crews work to make travelling safe and comfortable for all travellers, particularly families, the crew made the appropriate decision to return to the gate in the interest of safety."

But Blackwood said she had a window seat, so it wasn't possible for her son to be in the aisle of the plane.

While waiting to be put on another flight to Vancouver back at the San Francisco airport, the singer asked United employees for an explanation.

A video of her speaking to another employee was posted to YouTube. In it, the employee said she was shocked and had never heard of a mother being forced off due to a crying child.

Blackwood was eventually told by a supervisor that she was asked to leave because she refused to put a seatbelt around her son's lap – a claim she disputes.

"If I had the chance to put a seatbelt over him I would," she said, noting that she'd do "anything" so as to not delay the flight.

Blackwood was eventually put on another flight and reached Vancouver at about midnight. She said she had no problems on the second flight.

Since arriving in Vancouver, Blackwood said she's received emails from other passengers on the flight offering to corroborate her story, as well as sharing words of support.

She said she'd like some sort of compensation from United, as well as a formal apology.

She hopes that this situation will serve as a message to other travellers, particularly those who aren't parents or who aren't used to being around young children.

"There is no reason why any mother should be apologetic to the people around her because her baby is having a hard time on a flight," she said.

"They're not adults. They are not always consolable the way that people think that they are."