The expression in the title refers to a style of New England architecture. It's a uniquely North American expression of the connected farms found in England and Wales, adapted for New England farmers' needs. In the beginning, at least, the big house was the main living area of the farmstead and the little house was a connected kitchen. Behind these comes the back house or carriage shed and the livestock barn. I've read that these units often were built at different times, but connected to ease winter chores. Over time the units might have been given other uses, including housing cottage industries that provided income in winter.
The image at top was of a connected farm in a small village in Maine. The second is in a town in Vermont, a reminder that in the 19th century and before even city folks kept horses for transportation.
We have no such configurations in the southern mountains, although we see echoes of it in architects' rendering of modern homes using a New England style.