'Breaking Dawn' Swear Jar: Who Put In The Most Cash?

SAN DIEGO — When Mackenzie Foy joined the cast of "The Twilight Saga: Breaking Dawn - Part 2," it meant the rest of the actors on the project needed to be on their best behavior. But were they? Not according to the 11-year-old actress, who informed MTV News during our Comic-Con live stream that her swear jar had quite a few donations.

"It was a bit," Foy said with a smile when asked how much money she made, adding that she donated it all to St. Jude Children's Research Hospital. "Everybody cussed a little bit, but I'm not going to say who said the most, because I don't want anybody's mommy to hear, because I know if me or my brother says something, we get in trouble."

Even though Foy's onscreen parents, Robert Pattinson and Kristen Stewart, had a hard time keeping their F-bombs under control, they all became very close during their time working together. The fact that they feel the need to protect Foy was evident during Thursday's "Breaking Dawn" panel, but the young actress said they don't act particularly parental toward her.

"They're really, really sweet. They weren't so much a brother/sister, they're more ... super sweet friends. It's like the friend that you tell everything to. Like, that kind of friend," Foy said. "They're the sweetest, nicest people. They're super sweet, they're always kind, and they will never be in a bad mood."

This is Foy's first Comic-Con, and she said she is feeling a "mixture of excitement and happiness." We asked her to explain her experience auditioning to be Renesmee Cullen, which must have been a pretty surreal time for the then-9-year-old star. It was her first movie role, and she could remember exactly what happened the moment she found out she got the part.

"I was in Hawaii filming 'Hawaii 5-0.' So I was in my hotel room, I just literally got done with school, and I got a phone call," she said. "They told me, 'Mackenzie, you got Renesmee, you're in "Twilight!" ' And I was like, 'What? What'd you say?' And they were like, 'You got "Twilight!" ' And I was like, 'My first movie! Oh my gosh!' And I was just freaking out and I wanted to scream, but I was in a hotel."

Stick with MTV as we bring San Diego Comic-Con to you with wall-to-wall convention coverage from the panels to the streets. Hosts Josh Horowitz and Steven Smith are onboard for live broadcasts on fan-favorite movies, comic creators, TV shows, cosplay, gaming and more!