The idea for "Mother Simpson" was pitched by Richard Appel, who decided to do something about Homer's mother, who previously had been mentioned only once. Many of the writers could not believe that an episode about Homer's mother had not previously been produced. Part of the fun of an episode about Homer's mother for the writers was that they were able to solve several little puzzles, such as where Lisa's intelligence came from. The ending shot with Homer gazing at the sky was decided at the table read, but the drawing at the end was inserted by David Silverman because it was felt that the scene was so touching that no other lines were needed. As a result, no promos were aired over the credits during the original airing of the episode. Bill Oakley has admitted that he always gets teary-eyed when he watches the ending.