Angelina Jolie and Brad Pitt struggle to control their kids

Angelina Jolie and Brad Pitt are losing control of their four children, it has been claimed.

The Hollywood couple, who have 3 adopted children, Maddox, 6 Pax, 4, and Zahara, 3, as well as 22-month-old biological daughter Shiloh, are struggling to cope handling the four very different personalities, which all seem to clash.

A source claims that Maddox, who Angelina adopted from Cambodia in 2002, is constantly pushing Pax around in an attempt to show him who's boss. "But Pax is no wimp, and he fights back," the source tells Star magazine.

But it's Zahara "who really rules the roost", says Star. "She screams and shouts at the boys when she doesn't get her way," says the source. Not even little Shiloh is safe. "Z is always pushing or scratching her." And she even has the battle scars to prove it.

Zahara's picking on Shiloh is usually motivated by food. "Z once clawed Shiloh's cheek after she tried to take her cookie," says an insider who witnessed one incident. "She's always pulling on Shiloh's hair so she can steal her food."

And recently, while Shiloh's three older siblings played rough, she got knocked down and chipped a tooth. "Angie gets worried when Shi plays with them," says the insider. "She always comes back with a scraped knee or a fat lip!"

Another source claims food is a problem with all the kids and blames much of their rowdiness on a poor diet. "They eat fast food, pizza, chips and sugary soft drinks," says the source. "Brad and Angie let them eat what they want because it brings harmony to the chaotic household."

And to add to the problem, the children are also allowed to go to bed whenever they want. "Because bedtime is whenever the kids feel like it, they get overly tired and cranky. Brad and Angelina don't like to be too strict."