Another of my Portland finds. As far as the term "lassie" goes, I haven't any way to tell if this is a boy or girl collie, but so far everyone I've shown this to says "Oh, a Lassie dog."
The little black corner is stuck on there, so you get to see it too.
I get the feeling this is a dad, dog and kids snapshot, Mom or somebody capturing a sunny day they all got to spend together. The dog clearly was beloved enough to get front and center in the photo.