If you know a little about Frank Lloyd Wright than you might know the smallest house he ever designed with a dog house known as Eddie's House.
The dog apparently didn't have a sense of good design and, the story goes, hated his new home. The Wright dog house was eventually torn down.
However, Letters of Note has the correspondence that started it all. I can see why it would have been hard for Wright to turn down the request. I wonder if he was paid in paper route money or if he sent the designs out of the goodness of his heart.