Sean was last seen playing with his ball outside of his family's residence in the 300 block of Water Street in Watertown, New York on May 17, 1984. His baby brother was also outside. Their mother went inside their house to answer the phone at approximately 5:30 p.m.; when she returned less than two minutes later, Sean had disappeared, but the baby was still in his playpen. He has never been seen again. Sean has a birthmark, one inch in length, between his shoulder blades, and a scar and another birthmark on his forehead.