Amy and her stepfather, Marshall Midden, stopped at the Holiday Inn gasoline station in Osseo, Minnesota at 4:30 p.m. on August 5, 1989. They were on their way home from a day trip to the family farm at the time; they lived in Maple Grove, Minnesota. Midden went inside the station for a brief moment to use the toilet. When he returned, he saw that she had disappeared from their parked vehicle. She has never been heard from again.

Authorities initially believed Amy ran away from home. She had done so once before after packing clothing, but had only been gone for a day. She is no longer considered a runaway; it is thought that Amy may have had a seizure while Midden was inside the building and became disoriented as a result. She may have walked away from their car afterwards.

Amy remains missing and her case is unsolved. Her family has kept the same telephone number since her disappearance in case she attempts to contact them. Maple Grove police are investigating her disappearance.