Sailor Brinkley-Cook Says Her Mom 'Didn't Fully Know the Pain' She Felt Battling Body Image

Sailor Brinkley-Cook is continuing to speak candidly about her ongoing struggle to love and accept her body.

In her first live interview about the topic, Brinkley-Cook appeared on Good Morning America Friday where she opened up to ABC News correspondent Deborah Roberts about her vulnerability when she's off-camera.

"I have this awful feeling that if I’m not skinny, I’m not worth being celebrated and I’m not worth being praised,” the 21-year-old model said.

"I’ve been just been having these moments where I look in the mirror and I’m just disgusted with myself," she revealed, even when it comes to "the tiniest little things like a roll on my stomach, a little pooch on the bottom of my stomach.”

RELATED: Sailor Brinkley-Cook Has Been Struggling with 'Body Dysmorphia' and 'Eating Disorder Tendencies'

Good Morning America Twitter Sailor Brinkley-Cook

Brinkley-Cook, the daughter of model Christie Brinkley, admitted that growing up and being compared to her mother was not always easy.

“I grew up a little bit overweight and I felt the weight of my overweightness on me constantly from people teasing me and people looking at me differently,” she explained.

"It’s just crazy how that can really just shut down your self-esteem,” she said of constantly being sized up to her look-alike mother.

Sailor Brinkley Cook and Christie Brinkley

The model also revealed that her mother wasn't fully aware of her daughter's battle with body dysmorphia.

"My mom didn’t fully know the pain that I was going through when I was at my worst," Brinkley-Cook told Roberts.

The former Dancing with the Stars competitor, who first opened up about her struggles in a lengthy Instagram post on Sunday, said she first developed an eating disorder around the age of 15.

"I was looking up at all these major figures in modeling that are size double zero and they’ve got these thin legs and these tiny waists,” she explained. “I was seeing them being so celebrated by everyone everywhere and being wanted by all the boys and all that greatness that comes around being this tiny supermodel. And I wanted that."

Around the same time, which Brinkley-Cook said was the "pinnacle of her eating disorder," she recalled feeling confident with herself because of how thin she was.

The model said, "I remember feeling so happy with myself because I had a thigh gap."

RELATED: Christie Brinkley Shares Body-Positive Message with 1977 Bikini Pic That 'Caused a Stir'

Earlier this week, Brinkley-Cook shared she's been "so down on [herself] recently" and wanted to shed light on her years-long battle with her body.

"I’m so f—ing sick and tired of the photoshop 👏🏼," Brinkley-Cook wrote, quoting rapper Kendrick Lamar's "HUMBLE" before continuing in her own words: "Crying about my cellulite, letting the fat on my body ruin my day, getting mad that I’m not as skinny as I once was."

"The body dysmorphia and left over eating disorder tendencies have been coming in strong," she continued. "As I come into myself as a young woman my body shifts and changes by the month, the 'control' I felt I once had over it has been completely stripped away from me. Hormones, emotions, growing pains."

The model admitted that when she's on Instagram, she compares herself to photos of girls "that look perfect,” but now, Brinkley-Cook revealed that she is trying to focus on what her body can do.

"What I’ve learned is that I run every day. I go to the gym 6 times a week. I fuel my body with beautiful food. I am so f—ing LUCKY to have two legs and a healthy body that takes me through life," she wrote.

"Declaring that I have cellulite, and a stomach that doesn’t always look 'pleasant' (whatever the f— that means) and I am 100% imperfect human," she added. "And I’m proud as hell of my body! If you’re out there hating on yourself, stop!! Appreciate yourself. You’re body is so magical. That’s all. Have a nice day. 😌."