Mrs. Wallace was the wife of Luke Wallace.
Two days before Halloween, Mrs. Wallace returned home from the store with candy for the trick-or-treaters. Her husband Luke was feeding their baby. She put the candy away, telling him to stay away from it while she took the baby upstairs. As soon as she was gone, he got into the candy and ate one piece. He winced in pain and discovered a razor blade in his mouth. He took it out but then collapsed to the ground, spitting out another razor blade and spitting blood. Mrs. Wallace returned a few seconds later to find him dead on the floor.
The next day, Sam and Dean investigated, disguised as FBI agents and while Sam talked to the wife, Dean found a hex bag hidden in the kitchen. Mrs. Wallace said that her husband did not have any enemies and was not having an affair, and even if there was nobody could have killed him by putting razor blades in candy he might not even eat.