Sledge was last seen in Marysville, Washington on December 12, 1997. She was riding in a red four-wheel drive 1984 Toyota pickup truck with her boyfriend, Erik Lauren Mattison, during the late afternoon hours, and their truck got stuck in the mud west of Interstate 5. The two of them went to a friend's home on the Tulalip Indian Reservation on Quilceda Road to ask for help. The friend couldn't help them and they left. On December 13, Mattison returned to the friend's home to ask again for help. Sledge wasn't with him at the time. She has never been heard from again.

Mattison stated Sledge had separated from him and went to get assistance and never returned. He said he eventually got the truck out of the mud himself, but then it got stuck again elsewhere and he abandoned it. Authorities didn't find the truck until early January 1998. It was in a wooded area east of Marine View Drive and north of Waterworks Road. It was only then that police realized the vehicle had been stolen.

Sledge is considered to be missing under suspicious circumstances. Her case remains unsolved.