heat index," christie brinkley's daughter. She's following in her mom's footsteps. Sailor cooke, featured in "teen vogue." She sat down with her famous mom and deborah roberts, talking about the... See More
heat index," christie brinkley's daughter. She's following in her mom's footsteps. Sailor cooke, featured in "teen vogue." She sat down with her famous mom and deborah roberts, talking about the beauty business, and the pressure to fill her mom's high heels. And we have deborah roberts to fill in us in. Reporter: She's just a classic teenage girl. Modeling is the last thing on sailor cooke's mind last year. She was obsessed with term papers and zac efron. But somebody noticed that christie brinkley's little girl had grown up and inherited her mom's famous looks. She cruised her way on to the big screen in 1983, alongside chevy chase in "national lampoon's vacation." ♪ Uptown girl you know I can't afford to buy her pearls ♪ Reporter: And by the time she stepped out of that sleek rolls-royce, christie brinkley was more than just an uptown girl, gracing 3,000 magazines. But she's passing her beauty baton to none other than her daughter, sailor. Are you worried that people are going to be looking at you like the next christy? I think that's how they're going to view me by the world. I want to get my own identity. Reporter: The 15-year-old christie look alike, debuted in this month's issue of "teen vogue." Admitting she went through an awkward stage and wouldn't think about modeling. Then, sailor posted these side-by-side photos on her instagram. One year ago at the same time. #Transformationtuesday. What were you most excited about in that photo? Growing up, I guess. Puberty, to be honest. Reporter: You asked your mom about whether you should do anything specific to change your body, right? Yeah. Reporter: Should you diet? And she was like, no. You should be, like, careful. And you should be knowledgeable of what you're eating. But don't go too crazy. You don't want to turn out to be one of those kids that doesn't look healthy. It's about you feeling good. Not external pressure. Reporter: Pressure lots of teen girls feel. So, sailor jumped on the issue in "teen vogue" and took some heat for it. I'm not saying that skinny people aren't beautiful. You should find the thing you like about your and make it shine. That's so cute. Is that you or is that your mother? That's my mom. Reporter: It's easy to confuse mom and daughter. Look at their first photo shoot together for "bella" magazine. What was it like to work with your mom? I make laughter noises when i smile. She was embarrassed. She goes -- Reporter: And while modeling is a fun summer job, sailor says photography, her first love, is what she's passionate about. Nothing else really excites me. I always have my camera out. It's so surreal that I'm actually doing this and finding out who I'm going to be. Reporter: Christie is making it clear that school, not modeling, is going toate sailor's schedule this fall. But this train may be hard to stop because she's got a claire's campaign coming out. And now, a celebrity tour to protect african elephants. She's very sweet, guys. She wants to use her shine to do some good in the world. So, she gets it, I think. She seems like she's very grounded. Thanks a lot, deborah. Coming up next in our "heat
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