Michael Sam ufeffsays he's not convinced his older brother is dead after going missing in 1998 -- and now he's contacted a famous psychic to find out once and for all.
Sam met with Tyler Henry -- star of "Hollywood Medium" -- and explained the situation ... saying he was only 9-years-old when Julian Sam (a teenager at the time) mysteriously disappeared.
Sam says his family pronounced Julian dead two years later -- but they never found his body ... and Michael says he believes there's a chance he's still alive somewhere.
Enter the psychic .