Size 22 Mississippi mother Tess Holliday has proven her critics wrong and, after years of trying, been signed by a modelling agency who is hailing her as the largest professional plus-size model in the business.

'I feel like it's breaking ground,' the 29-year-old told The New York Daily News.

'This is a milestone. I never could have imagined that I could be here.'

Holliday endured years of bulling during her small town upbringing in Laurel, and the abuse she suffered would continue through to her adult life and career.

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Pushing the envelope: Size 22 mom Tess Holliday has been signed by MiLK Model Management, who are hailing her the largest professional plus-size model in the business

Success: Tess Holliday's modeling career is on the up. She is seen here with her husband, Nick Holliday

Provocative: Holliday has built her name on social media over the years, and now has an agency

'It took a really long time to get over things that had happened to me during the vital years of my life,' she said.

As a teenager, Holliday traveled to Atlanta for a model casting, but, at 5 feet 5, was told she was too short and too big.

'My mom always encouraged me,' she said.

'But the rest of my friends and family thought I was nuts.'

Holliday puts her determination down to her activeness.

Lazy she is not.

Holliday has a nine-year-old son, a husband, she works out with a trainer, and is now getting a steady stream of work.

'I never sit down. If I'm not shooting twelve hours a day, I'm out doing errands and going to meetings,' Holliday told The Daily News.

Sexy: The 29-year-old is being hailed as the largest plus-sized model in the business

Unabashed: Holliday's career has proven wrong the bullies that have followed her through life

Her big break came in 2011, when A&E chose her to be the face of their documentary series, Heavy, after discovering her online.

Since then she has modeled for Domino Dollhouse, SWAK, Jessica Louise Clothing, Evil Pawn Jewelry, Black Cat Bikinis, and more.

In 2013, Holliday started a social media movement she called #effyourbeautystandards, a salute to pushing positive body image.

That same year was named by Vogue Italia as one of the top six plus-size models in the world.

Last year she became engaged for Australian businessman Nick Holliday, whose surname she has now adopted.

Happy: Holliday is a mother and a wife and says she works out each week with a trainer

Love: The model became engaged to Australian businessman, Nick Holliday, last year. They live in LA

But her biggest break yet came on Thursday, when MiLK Model Management announced they had signed Holliday to their plus-size arm, Curves.

It was a strange move, given Holliday - at 260 pounds - is the shortest and largest model in their portfolio.

Plus-size models are typically size 8 to 16 and at least 5 feet 8 inches.

The agency said they cottoned on to Holliday because of her vast social media influence, especially on Instagram.

The decision to sign her has been lauded.

'It's radical to have an agency willing to stand behind someone and push the envelope about what way models have to look,' QueerFatFemme blogger Begin Branlandingham told The Daily News.

'Bodies come in all shapes and sizes.

'A good model has more to do with how she works in front of a camera then what her height and weight proportions are.'

Peace: Tess Holiday has 308,000 followers on the social media site Instagram.

Holliday's trajectory is a triumph over her critics and her bullies.

Perhaps in a 'that-will-show-them' move, she has a tattoo of Miss Piggy on her right arm.

But success does not nastiness, and Holliday still receives plenty of negativity.

'I'm always still that 13-year-old girl in Mississippi who people told I wasn't good enough,' she said.