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They might have tried to ban the rest of the media from the country but Brad Pitt and Angelina Jolie haven't been shying away from all cameras - they've secretly been filming their own documentary about their stay in Namibia.

The couple have been filming since they arrived in the country in early April and will keep filming until they leave in a few weeks - including footage of their new baby daughter, Shiloh.

A source has revealed: "Brad and Angelina want to put out a serious social documentary about all the great things the country has to offer."

"Angelina is in love with Namibia and wants fans to learn more about it and experience what she has experienced."

"Maddox is in the film along with Zahara, and they have agreed to include some footage of their new baby."

"They know that any documentary which includes anything personal about their lives will help them get their message across."