Some family members and friends believe Adam Sharp — the 23-year-old veteran Marine reported missing from Highland Park on New Year's Eve — may be off his medication and avoiding being found.

Bob O'Brien, a former Edison resident, has been staying in the area for several days to help with the search, hoping recent reports Sharp may be in Woodbridge pan out. O'Brien said his longtime girlfriend, Brenda Valentino, was a "second mother" to Sharp during his teen years, after some difficulties at home. They've been working with Adam Sharp's mother, Trudy Sharp, in the search, he said.

But O'Brien said they've seen signs Sharp is ducking those searching for him.

Over the weekend, O'Brien said, he and others knocked on several doors on Mary Avenue in Woodbridge, and were told by residents they'd seen someone matching Sharp's description in the neighborhood.

They put up hundreds of flyers on that street and others nearby Saturday, he said. Early Sunday morning, O'Brien said, he went outside and found all the fliers had been taken down. Flyers were removed from a nearby wooded trail as well, O'Brien said.

"I think he's living with someone on that street," O'Brien said.

The group put up more posters on Sunday, hoping they might see Sharp if he came out to remove them, O'Brien said. But so far, they're still up.

Sharp was last seen in late December, walking with a friend, his sister-in-law, Samantha Johnson has said. He did not bring a wallet or ID.

Johnson has said it's possible Sharp — a practiced long-distance hiker — was trying to walk to North Carolina, where he lives on a farm.

O'Brien said Sharp was always dismissive of the trauma he suffered overseas, and only found out after some time that Sharp had seen several friends die while serving in Afghanistan.

He said Sharp didn't like to take the medication prescribed to him for post-traumatic stress disorder, preferring instead to take "organic" treatments.

"I've been staying up every night," O'Brien said. "I'm not leaving until we find this kid. He's been like a son to me. We need to know he's safe."

Sharp is 5 feet and 8 inches tall, weighs 130 pounds, and has green eyes and brown hair. He has a full beard and was last seen wearing pajama bottoms and a jacket.

Calls placed to Highland Park police about the state of the search Monday had not yet been returned.

Authorities are asking anyone with information about Sharp’s whereabouts to call either the police department in the area where he is seen, or Highland Park Police at 732-572-3800, ext 4263.

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