What was the reason Vivienne Jolie-Pitt was cast in 'Maleficent'?

Angelina Jolie revealed the reason that her daughter Vivienne Jolie-Pitt was cast in 'Maleficent'.

She explained, "We think it's fun for our kids to have cameos and join us on set, but not to be actors. That's not our goal for Brad and I at all. But the other 3- and 4-year-old [actors] wouldn't come near me. Big kids thought I was cool- but little kids didn't like me."
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"So in order to have a child that wants to play...it had to be a child that liked me and wasn't afraid of my horns and my eyes and my claws. So it had to be Viv."

"I had a friend come with their children and when I met the kids, the kids froze and screamed so much that I had to go wait in my trailer," Jolie told EW.
"When (son) Pax saw me for the first time he ran away and got upset - and I thought he was kidding, so I pretended to chase him until I actually found him crying."
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"I had to take off pieces (of the makeup) in front of him to show him it was all fake and not freak him out so much."

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