Frank probably lives in one of those old Nebraska farmhouses where one of the 15x17 bedrooms was made into a bathroom after the outhouse blew away. 
Actually, it appears to be about 12x12, but remember, I've been taking grief for my lousy perception of space and distance--a characteristic of those raised in the Sandhills of Nebraska.
I say "12x12" because I'm 6'2.5" tall, and it appears to be twice my height, both ways.
The original four rooms of this place were built during the 1880s; the settlers (who came in 1875) quite reasonably took care of the pigs first, before their own ease and comfort. They were living in a sod house while the pigs lived in a super-deluxe state-of-the-then-art barn and other outbuildings. The pigs would enable them to survive and flourish, so best to take care of the pigs first.
The bathroom was added in 1891, indoor plumbing. If one's looking at the floor-plan, it's a "tab" that sticks out on the west side.
The fixtures however were replaced during the 1960s with things more appropriate for an old woman who was determined to live out here until she died (which she nearly did).