Looking for brother born 4/1988

I am looking for my half brother for several reasons. He was born on or around April 8, 1988. I am his older sister. I will have to ask my grandmother what agency branch he was adopted through. But his birth mother was 20-21 when he was born not sure which last name she used. It was either pary or Johnson. If any one has any information please let me know. Thank you!