Ashley Graham Reveals She Combo Feeds Twins, Opens Up About 'Stressful' Breastfeeding Journey

Ashley Graham Instagram

Ashley Graham is getting real about feeding her babies.

The model, 34, speaks with PEOPLE about her work with Bobbie as a founding member of the Bobbie MotherBoard, and her historic new billboard showing her combo feeding twins Malachi and Roman, 8 months — making her the first parent to ever to combo feed babies with breastmilk and formula on a billboard.

The supermodel mom, who also shares son 2-year-old son Isaac, with husband Justin Ervin, admits that the feeding "journey with the twins has been an interesting one."

"I thought that I would easily be able to breastfeed without having to think twice about it. I knew that there was going to be a little bit of actual juggling that would have to be implemented because everybody and their mother told me that if I didn't feed the twins at the same time, I was never going to have any time for myself," she explains. "And sure enough, that's exactly what happened. I had to figure out how to do it at the same time."

Graham shares that she gave herself six months to give tandem breastfeeding the twins a sincere try, making sure to check in with herself "mentally and emotionally."

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Bobbie

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"The first week was so hard," she admits. "It was trying to figure out how to do it. They would latch. They would unlatch. I couldn't figure out the positioning."

Graham says she found success for about a week and then "all of a sudden it was like we didn't want to do it anymore and I felt defeated. I felt like what am I going to do? How am I going to feed my babies?"

Graham says she had to have "some internal conversations with myself" to get through the tough moments.

"I remember telling myself, 'It's okay if you have to use formula. Don't worry. You're not failing as a parent.'"

Bobbie

Ultimately, she found that combo feeding was the best choice for her and her babies.

"I'm so glad that I decided to do combo feeding because it was a stress that was lifted off of my shoulders and it relaxed me enough so that I was able to breastfeed the twins with more ease and it wasn't such a stressful situation for all three of us."

During Graham's conversation with PEOPLE, the mom of three saw her New York City billboard for the first time.

"I just want people to know that there's there's no one size when it comes to feeding your babies," she says. 'I have championed all kinds of different bodies in fashion and media to be represented, and that's exactly what I want to do here.

Graham says that with feeding being "such a stressful situation," many parents feel "like you have to pick one side or the other."

"I really want this campaign to show that you don't. You just have to pick what's best for you," she says. "I joined forces with Bobbie to evolve in this conversation and shake the stigma around how we are feeding our babies. There's no way no one way is better than the other."