friend is looking for his birthmother he was born 11/25/1993

hello my name is tanya and i'm helping my friend to try to find his birthmother His name is "Jonathon". His adoptive parents kept the name she gave him and the spelling. He was born In York, Pennsylvania on 11/25/1993. He knows that his biological father is deceased. He was told that his birth mother wanted to see him when he turned 18. since he is 18 now he wants to find her. His adoptive parents are Robin&Rick Avila. any info will be greatly appreciated.