Escape From Neverland! Inside Blanket Jackson's Top-Secret Summer Getaway

Does Blanket Jackson have a secret relationship with his birth mother? The reclusive fifteen-year-old surfaced Saturday night in the suburban outskirts of San Diego -- where the woman who gave birth to him has long been rumored to live.

Onlookers were stunned to spot Blanket and his brother Prince, 20, catching an 8 pm showing of War for the Planet of the Apes at Cinepolis La Costa in Northern County San Diego on July 22. (The Jacksons had their own pet chimpanzee, Bubbles, up until 2003.)

Excitedly chatting as they waited in line to enter the theater, the boys were accompanied by one of their cousins, a few friends and a mysterious adult male handler who had purchased the group's tickets.

"He didn't look like anyone who's ever been photographed with the family in the past," an eyewitness told RadarOnline.com. "And it almost seemed like he didn't know the boys very well. They weren't interacting with him very much at all."

As for Blanket, "He was shockingly thin," the eyewitness said. "He must have been about 5'9" or 5'10" and he looked like he weighed about 120. Totally skin and bones."

Why the trip to San Diego, more than two hours away from the boys' hometown of Calabasas?

Unlike his L.A-born siblings, Blanket was born at the Grossmont Hospital, nine miles outside of downtown San Diego.

Although his birth mother is not named on his birth certificate, the woman who carried him was reportedly a Mexican nurse named "Helena," who was said to live in the suburbs outside of San Diego.

Michael never confirmed the identity of his son's mother before his death in 2009.

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