Sadie Robertson has been a fixture on her family’s reality show, "Duck Dynasty," for years, but the fashion designer and reality star makes her feature film debut in the new faith-based drama, "God’s Not Dead 2."

“It was so cool,” Sadie, 18, gushed to ET at the film’s premiere last week. “I've been kind of easing my way into movies and this was the perfect way to do it, with something that means something to me.”

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The Robertsons have always been outspoken about their strong Christian beliefs, and Sadie’s mother Korie told ET that faith is what gets the family through “the good times and the bad times.”

“It's not something that likes, 'Oh it's there on Sunday then it's not there,’” Korie explained. “I think it permeates every part of our life.”

For Sadie, her faith helped her through an impressive run on "Dancing With the Stars'" 19th season, in which the reality star finished as the runner-up behind Alfonso Ribeiro.

“Without that faith during that show, I definitely couldn't have made it through,” she admitted. “It was just a crazy experience and God just really took me the whole way.”

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The model and actress is also leaning on her faith and family as she deals with a recent split from longtime boyfriend Blake Coward. According to her mom, however, Sadie is keeping focused on her career.

“She's gonna focus on this movie, and on what we're doing with 'Duck Dynasty,' and all the amazing opportunities she's got going on right now,” Korie told ET.

Next up for the whole Robertson family: a wedding! Sadie’s older sister Rebecca is set to tie the knot later this year, though the clan is staying tight-lipped about details.

“She's going to do a destination wedding. We can't tell where but it will be this year,” Korie revealed. “The whole family is really excited about it.”

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