Christie Brinkley didn't know her bad her daughter's body image issues were

The 21-year-old star told Good Morning America: "My mom didn't fully know the pain that I was going through when I was at my worst ... 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. It's just crazy how that can really just shut down your self-esteem."

Sailor recently slammed body ideals on social media, admitting she had been "so down on herself recently".

She wrote: "I've been so down on myself recently. 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. 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. I go on instagram and scroll through photos of girls that look 'perfect' ... shiny skin with not a bump to be seen, tiny little waist and thighs that look like chopsticks.

"And i compare myself, as if how someone on an app on my phone looks should directly correlate to how I feel about my body? 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. I’m so tired of thinking anything that makes up ME is something to be ashamed of. (sic)"