For some reason people seem to like little girls with big dogs. I can't blame them, I partial to the dogs, myself. Just ask Pickles.
There is a whole series of these cards, and I have a couple of them. Some of them have the same dog & girl, others are different. But the background and scene are the same.
I've noticed that postcard publishers do that. You'll see the exact same pictures in different formats sometimes. Sometimes you'll see the same picture but with a different caption. I think I have a postcard which somehow placed the Rocky Mountains in Kansas.
This is a pretty postcard, early 20th century, divided back. On the back the word "post card" is printed in about 20 different languages.
Not sure what kind of dog it is, but it's pretty good size.