Who is Betty and Leo Glick from Four to Score and what is their importance?

Betty and Leo Glick are Kuntz's aunt and uncle. Betty and Leo live on the other side of Kuntz's duplex and appear friendly to Stephanie, at first. However, after a time things begin to change and their behavior becomes suspicious. Despite this, Stephanie never imagines that Betty and Leo are criminals until she breaks into their side of the duplex hoping to find information on Kuntz's whereabouts. While in the house, Stephanie discovers a dead body in their basement.