A 10-year-old autistic boy, his service dog and his grandfather had to leave the Corner Brook Walmart on Thursday after an employee refused to accept the dog's brightly coloured vest as evidence the animal was working, according to the boy's grandmother.

"He thinks Walmart bullied his dog," said Janet Butt, about her grandson, Maverick Butt, and his dog, Abner.

Janet Butt, her husband, Maverick and Abner, Maverick's service dog, were in Walmart's Lego aisle, looking for a new toy. The boy was going over each set carefully — "He analyzes every box," Butt said — and the dog had lain down to rest on the floor.

That's when a salesperson approached and asked what the dog was doing, Butt said.

Butt told her the dog was working, and the salesperson asked to see the dog's papers, she said.

"I'll admit that I'm slow on the uptake," she told CBC's On The Go. "I'm like, 'What?'"

Butt then pointed out the dog's service animal vest and said again that the animal was working, she told CBC.

"She said, 'I need to see his papers, it's protocol,'" she said.

"And I said, 'No, it's not.'"

This is the vest Abner was wearing at Walmart in Corner Brook on Thursday. (Provided by Shannon Butt)

Butt said that very Walmart store is where Abner was trained to be in public places.

"I got certified with my public service access at that store," she said.

"I was never asked to provide paperwork, identification, nothing."

'When the volcano starts to rumble'

The salesperson "started to approach more aggressively" and said she didn't accept the vest, Butt said.

And that's when Maverick Butt began to get upset, she said.

"The boy starts saying, 'Accept? Accept?'" she said.

"I pulled out my phone and I say, 'I'm going to record you.' And she insisted, she said, 'I don't care, I don't care, I need to see those papers.'"

He thinks Walmart bullied his dog. - Janet Butt

Knowing that things could get worse if Maverick got more agitated, she sent him out of the store with Abner and her husband.

"In my household, when the volcano starts to rumble you try to quiet the rumble."

She stayed back to try to speak to a manager about the incident.

Abner keeps Maverick alive, grandmother says

Butt says Abner is often responsible for keeping Maverick alive. The boy is non-verbal and has no sense of fear, she said.

"He has bolted so many times."

Abner, she said, keeps him calm and stable.

"Sometimes Abner has been the difference in Maverick living."

Abner's vest indicates he is a service dog for autism. (Provided by Shannon Butt)

Abner was recommended when Maverick was first diagnosed, and Butt said the family was blessed to get the dog, given that service dogs are in high demand but in short supply.

Abner and Maverick are now very close, she said.

"It became a love story."

Sign on the door says service animals are welcome

Butt said she still has not received an adequate response from Walmart about her concerns, and that nobody from the company has contacted her.

A representative from Walmart Canada replied to Shannon Butt's Facebook post Friday to apologize and invite both Maverick and Abner back to the store.

"Walmart is committed to providing a safe, convenient, and dignified shopping experience for its customers with disabilities," the reply from the official Walmart Canada account read.

"Service animals are permitted to enter Walmart stores as companions to customers with disabilities. We're sorry this happened."

Janet Butt notes there's a sign saying service dogs are welcome hanging up at the store's front entrance.

She wants to know why Walmart is claiming to be inclusive but employing people who don't understand service dogs.

As for Maverick, she said he has his own concerns about the incident.

"He feels that Walmart owes Abner an apology."

Walmart has not returned a request for comment from CBC News.

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