Mayberry disappeared from Kenedy, Texas on April 1, 1999. He was last seen leaving his home with another man. The man knocked on his door at 11:00 p.m. and although Mayberry said he did not know him, he left with him anyway, telling his niece he was going to the store and would be right back. She said he was shaking at the time. Mayberry was carrying a black patent leather clutch purse at the time of his disappearance; it contained $20 to $30 in cash, a black compact and a package of Virginia Slim cigarettes. He never returned home.

At 2:30 a.m. the next morning, two men in a truck with a loud muffler tried to get into the house with Mayberry. His niece told them he wasn't home, and they laughed. It is unclear whether the men were connected to Mayberry's disappearance. He has never been heard from again.

Mayberry is described as a trusting, friendly individual. He left without his medication and he has not collected any disability payments since his disappearance. His disability checks were his only source of income. As Mayberry is a homosexual and cross-dresses, a hate crime may have lead to his disappearance. Foul play is suspected in his case which remains unsolved.