Mystery Family from St. Charles, IL

A photo of an unknown family. When I moved into my house in St. Charles, IL, I found this small picture outside, under the porch. The picture was crumpled and torn, and I restored it as well as I could. I have no idea who these people are, and neither do the people who lived in the house before me. Anyone recognize them?

Who are these people?
When was it taken?
Where was it taken?