Brad, Angelina: Double Trouble!

Angelina Jolie and Brad Pitt admit that bringing up twins is quite "a challenge" that leaves them exhausted often. The couple welcomed Knox and Vivienne into their brood of four in June 2008.

Angelina says, "We're exhausted a lot, because it's twice as hard with two babies than with one." But she adds that the thrill of raising twins makes the hard work worthwhile! "It's twice as much fun, too. When you look at them, it's like they were made for each other. They smile at each other, sniff each other, touch each other. It's just beautiful."

So who do the twins look like? "Well, Knox looks more like Brad and Viv more like me. They're totally sweet. Knox is more the quiet one, very relaxed, while Viv is a little more aggressive and loud."

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