Sofia Vassilieva is a freak of nature. Most child actresses are, but in her case that's meant as a compliment. What other teenage girl would shave her head for a job? Dakota Fanning wouldn't—and we know that because she reportedly lost the role of a cancer-stricken teenager in My Sister's Keeper after director Nick Cassavetes (The Notebook) demanded that she go bald for the part. He then auditioned Vassilieva, who was more than happy to make the sacrifice. On Valentine's Day, Vassilieva marched right into a salon and had her waist-length brown locks chopped off. She even saved the hair, so it could be made into a wig for her other day job, playing Ariel Dubois on the TV drama Medium. Wasn't she scared? Let's forget about the career thing—Vassilieva is still dealing with the harshest critics of all: high-school girls. "Of course, of course, your hair is so much of who you are," says Vassilieva, who is 16 and about to enter her senior year. "There was concern about whether my head was going to be round or lumpy. Up until the point I shaved it, I was hysterical." (Article continued below...)
Now it's your turn to cry. My Sister's Keeper is the biggest sobfest of the summer (and that's meant as a compliment too, kinda). Based on Jodi Picoult's bestselling novel, it's about a young girl named Kate (Vassilieva) who is diagnosed with leukemia, so her parents (Cameron Diaz and Jason Patric) decide to have a second daughter, Anna (Abigail Breslin), to serve as an organ donor and save her big sister's life. The premise is straight out of a Lifetime TV movie, and the screenplay—with its multiple voice-overs and courtroom scenes—hardly does it any favors. And yet, I'm almost embarrassed to admit this out loud: I was entirely sucked in. Onscreen, Vassilieva is like a mini Meryl Streep projected on Katherine Heigl's cherubic face, and her performance is about the most gut-wrenching thing you can imagine from a popcorn summer movie. "She is so wonderful," says Diaz. "I think about it and it gives me chills."
Vassilieva is the only child of two Russian scientists, which might explain why she's so thoughtful and why she's already finished a year of calculus at school. "My parents have always been open to me trying new things," she says, "whether it's yoga or ballet or tap or jazz or piano or horse riding." When she was 7, she started modeling. By 8, she had an agent and was acting. Her first big break: getting cast as Eloise opposite Julie Andrews in Disney's Eloise at the Plaza movies. "Having Julie there as a teacher and role model, I learned how to behave on a set, how to hold my ground, how to be incredibly gentle with people," she says. "My set etiquette came from her."
It's harder to figure out where her performance in My Sister's Keeper came from. Vassilieva herself can't really explain how she created the character, though she says it did require a lot of work. "For me, I'm big on research and knowing facts," she says. "I went to hospitals and met this sweet girl who was"—by total coincidence—"watching one of my Eloise films when I came in. She was painting and sharing pictures of herself. That kind of light she had four days after a major medical procedure—that is something that struck me as incredible." The role was so difficult that Vassilieva regularly cried between takes (though her character hardly tears up in the movie) and she didn't want her parents on set, not wanting them to see her so vulnerable. The hardest part about the whole shoot wasn't shaving her head, but shaving her eyebrows. "The eyebrows can't be a fashion statement," she says. "People stare, or they don't, which is worse. It's like you've already left, in a way. You're very isolated. That's what made the idea of cancer very real."
Vassilieva has a big reality check of her own coming up: college. She's definitely going next year. "Absolutely," she says. "College is one of the things I worked my butt off for in the last three years." She'd like to study Russian literature and poetry and maybe modern dance, but you should study her face now, because you'll see plenty of it in the future. At the New York premiere of My Sister's Keeper, Vassilieva runs up and down the red carpet greeting her cast members with a smile that shines brighter than the flashbulbs. Her hair has grown back, and she's wearing a silver Dolce & Gabbana dress that shimmers like an astronaut's spacesuit. "With no hair and eyebrows, I kind of look like an alien [in the film], so maybe we were going for that outer-space vibe [tonight]," she says. "No. I just thought it looked gorgeous. I saw it on the racks months ago and we weren't even looking for a premiere dress, and I [said], 'That's the one!' It fit perfectly. I'm so proud of this night." Kid, you deserve to be.