Angelina Jolie and James Haven in 2005 (Paul Hawthorne/Getty Images)
"There is no question Angelina makes a difference in our world by bringing awareness to so many causes," he told E! News. "Her compassion for humanity alone always makes me honored to call her my sister."
Of course, the news that his sister carries a "faulty" BRCA1 gene, which greatly increases her risk of developing breast cancer and ovarian cancer, must have hit home for Haven as well considering both siblings watched their mother, Marcheline Bertrand, lose her seven-year battle with ovarian cancer. She died in 2007 at the age of 56.
Despite Jolie's medical issues, the siblings – who just spent time together on Sunday to celebrate his 40th birthday, according to their father, Jon Voight – are currently working on film project together. Haven said he will be directing "Court of Conscience," which will spotlight child advocacy laws, and Jolie will be producing it.
Meanwhile, Jolie's fiancé, Brad Pitt, stepped out for the first time since she bravely shared her story in a New York Times op-ed piece published on Tuesday.
Dressed all in black with his hair pulled back, Pitt visited Paramount Studios on Wednesday. Jolie has yet to be photographed since the news broke.
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