JENNIFER ANISTON has a secret half-brother that she's never publicly talked about or been seen with, but now his wild punk lifestyle is being revealed for the first time.

Alex John Aniston, 22, has the same father as Jennifer — John Aniston, but his mom is actress Sherry Rooney as Down Under mag New Idea interviewed friends and neighbors of the described "scruffy punk."

Unlike Jen, 43, who lives a luxurious and very public lifestyle, Alex — who goes by AJ — splits his time between Santa Cruz, Calif. as a "boho surfer" and northern Alaska.

"He had a mattress in the back of his van, always had the same pair of pants with 20 patches on it and only had three shirts," Samantha Robles, a body piercer  told New Idea.

"He just hung out in his van on the beach, and would come in all sandy."

Samantha's boyfriend told the mag, "Santa Cruz has a large population of transient punk kids, usually traveling north. When I talked to AJ last, him and his girlfriend were doing something in Alaska, like farming. I think her family had land up there."

Although Jennifer has never spoken of AJ, he did attend the Along Came Polly premiere in 2004 with his parents, reported

Despite AJ's efforts to keep half-sister's Jen’s ID under wraps it was a no-brainer secret in his Santa Cruz neighborhood.

"I figured out who he was when one day I saw the dad turn up. I had friends out back and AJ and John were going through the garbage can," former neighbor Rich Koslowski divulged.

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