Nichols Electronics has a monopoly on the ice cream truck music box market. When you hear the familiar sound of ice cream truck music ringing through your neighborhood, chances are extremely high that it’s coming from a box that Mark and Beth Nichols created. For decades, they’ve been in the business of evoking nostalgia and happy memories. Until recently, when it was revealed that one of the most popular songs on their boxes has a dark history. Today on Proof, we tell the story of how one small family business faced the biggest controversy to rock the ice cream truck industry.