EXCLUSIVE: Christie Brinkley gushes over 'beautiful family' title, reveals why son Jack is rarely photographed

Christie Brinkley is one proud mother!

On Thursday night, the 63-year-old supermodel and her 18-year-old daughter, Sailor Brinkley-Cook, attended the Harper's Bazaar 150th Anniversary event, presented with Tiffany & Co, in New York City, and ET talked with the mother-daughter duo about People magazine naming them the World's Most Beautiful Family of 2017.

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Brinkley called the honor "great," and was super excited that her 21-year-old son, Jack Brinkley-Cook, agreed to participate in the photo shoot as he's rarely photographed with the family. "He does his own thing. He doesn't like to take pictures," Brinkley explained, adding that some of her Instagram followers have been saying, "'Wow! Your son's gorgeous! Why don't you feature him?'"

"It's like, 'I try! I try, but he shies away,'" she explained. Sailor added that modeling isn't "what he's going for."

Jack is, however, interested in another part of the entertainment industry. "He's in acting school and he does improv," Brinkley noted. "He's very funny and I think there's a future there."

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When asked how they keep their family so grounded, Sailor shared, "We just don't really take ourselves that seriously."Brinkley chimed in, "You don't get away with much in our family."

Reporting by David Batista.

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