But Foy can handle it. She's just 10 years old, but already a seasoned professional.
Foy, who will play Renesmee, the vampire/human love child of Pattinson's Edward Cullen and Stewart's Bella Swan, already boasts an impressive résumé filled with advertising and television work.
The adorable Suri Cruise look-alike has done print ads for Mattel, Talbots, Guess and Gap, appeared in TV commercials for Burger King and BlackBerry, and guest-starred on Charmed and Hawaii Five-O.
Stewart, 20, has already given Foy her stamp of approval. She told MTV that upon seeing photos of Foy for the first time, she remarked, "That's so weird. She sort of looks like Bella, which is absolutely right."
Meanwhile, Pattinson, 24, will share an awww moment with Foy in Breaking Dawn by reportedly playing "Renesmee's Lullaby" on the piano for his onscreen daughter.
Foy's professional side was very much in evidence when she arrived in Vancouver this week for filming. As she signed autographs, PEOPLE asked her what she was looking forward to during the shoot. "Just working," she replied.
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