The Twilight Saga: Breaking Dawn—Part 2, the final installment of the $1.7 billion vampire franchise that made household names of its star-crossed leads, Kristen Stewart and Robert Pattinson, opens this month with a new featured player, 11-year-old Mackenzie Foy. Having appeared in campaigns for the Gap and Ralph Lauren, as well as commercials and TV guest spots, the Los Angeles native was already seasoned when she was chosen to play Renesmee, the half-human, half-vampire daughter of Bella and Edward (Stewart and Pattinson). Renesmee can transmit her thoughts to people just by touching them. “It was my first movie, so every single piece of it was fun for me,” says Foy, adding, “I’m not allowed to read the books, but I’ve seen the first and second movies. I closed my eyes in the second one.” With tween-worthy ambitions that include a junior black belt in Tae Kwon Do, she has no intention of slowing down her acting career. She already has her own fan site but is full of admiration for Kristen Stewart, of whom she reports, “She was so super-sweet, one of the nicest, hardest-working people I have ever met.” And what disciplinary device did she introduce on the set? “I had a swear jar, and it was so funny,” she explains. Asked who the worst offender in the cast was, she becomes tight-lipped: “I’m not going to tell!”