Supermodel Ashley Graham's Message to Little Girls: 'Perfection Doesn't Exist'

— -- Looking back on 2016, Ashley Graham never imagined she’d become the first full-figured model to land on the cover of Sports Illustrated's annual swimsuit issue.

“These are things that I never even dreamed that I could even touch. Because for so long, I was told, ‘No, you're not that girl. You won't ever be that girl,’” Graham told Robin Roberts in an interview airing on the ABC News special, “Game Changers,” tonight at 10 p.m. ET on ABC.

“Honestly, at the end of the day, what I want women to know is that beauty comes in all shapes and sizes. And that it should not define who you are," she said.

Graham shattered stereotypes and barriers this year – from the coveted SI swimsuit cover to TED talks, designing her own clothing line and being named one of Glamour's 2016 Women of the Year for her activism and body positivity.

Even Mattel, the creator of Barbie, recognized Graham's influence this year. The toy maker collaborated with her to make a Barbie in her likeness, embracing all of her curves.

"It was really important for me to have touching thighs because little girls need to know that perfection doesn't exist," Graham said.

But Graham didn’t always have her signature confidence. Roberts traveled to Graham’s hometown of Lincoln, Nebraska, where Graham first grappled with her weight.

"Pretty for a Big Girl"

"Growing up here [in Lincoln]," Graham said, "I was called the girl that was 'pretty for a big girl, the fat model.'"

She admitted to cutting out the size tags on her clothing when she was a teenager.

"It just hurt my feelings to have to look at it," she said. "And looking back on it I'm like, 'Why was I so caught up on a number? I was looking good.'"

Graham's mother Linda has always supported her daughter, even when she moved from Nebraska to New York City at a young age to pursue her dreams of becoming a model.

“She really let me just be me,” Graham said.

But the Big Apple wore on Graham. She slowly began to gain weight and wasn't working as much as she had hoped. Agents told her, "'OK, you're working. You're doing OK. But if you lost about 20 to 30 lbs., you could be on top of the world,'" Graham recalled.

When everything was going badly, she turned to her mother for guidance. "I call my mom and I just broke down. I was like, 'I can't do it anymore. This is not for me.'"

But her mother reminded her how much she'd given up to pursue modeling in New York. Graham said her mother told her on that phone call, "If you aren't changing your life, fine. But your body is supposed to change somebody else's life."

Her mother proved to be right.

“There's something to be said about just being vulnerable,” Graham told Roberts. “Every woman has gone through something in her life that has been an image issue or it has been something where somebody told her she's not good enough. And every woman can relate to that.”