The narrator describes his father as content with his lot as a farmhand for the first 34 years of his life. He would work, have a beer at the local saloon, come home, and feel content. He was
quite happy in his position in life. He had at that time no notion of trying to rise in the world.
After his marriage, however, he and his wife become ambitious—and we are led to believe it is his primarily due to his wife and the subsequent birth of his son. The couple decide first to run a chicken farm and, when that fails, to open a restaurant.
We learn that after having been content with his lot for so long, since ambition entered his life, the Father has become silent and discouraged. He has also become eccentric, treasuring above all else the "grotesque" eggs and preserved chicks he brings with him from the farm. The freakish chickens from the grotesque eggs don't last long, but Father preserves them in bottles after they die.
The Father also shows his eccentricity in his decision that the restaurant is not a success because he is not happy enough and must be more so. In fact, he decides that he and his wife must entertain their guests. This cuts so far against the grain of his personality that the attempt is a failure—but the Father still takes comfort in his grotesque eggs.
The Father can be read as a critique of the American desire to be ambitious and rise in the world. He is happy and ordinary as a farm hand. The desire to be more than he is makes him as grotesque as the eggs he collects and identifies with.