Mum becomes a novelist (ママ上は小説家の巻) is episode 150 of the 1981 anime.Mrs Mitsuba is trying hard to win first prize at the novel competition at the upcoming prize giving, but she doesn't know what to write.
Mrs. Mitsuba is writing words on a piece of paper. Kenichi comes in and asks his mother what she is doing; she explains that she is trying to write a novel to receive a prize at the upcoming literary festival, and that she was a well-known essayist before she met her husband Kentaru.
Later on, Kenichi and the rest of the Mitsubas imagine what their matriarch is going to write about; and assist with the housework. Mrs Mitsuba is moved by their support.
Later on, Kenichi and Shinzo come to Mrs Mitsuba's room to deliver her dinner, only to find their matriarch in a disgruntled state, struggling about what to write. She then paces the garden, worrying about her novel. Kanzo Hattori then steps in and uses a ninja spell on her so that she can find things to write about. This then inspires Mrs Mitsuba to a great degree.
Next day, Kanzo, Shinzo, Shishimaru, Kenichi and Kentaru are sitting in the living room when Mrs Mitsuba comes in with a draft of her book; they have chapters which feature the family's mishaps and secrets:
The first chapter features an intoxicated Mr Mitsuba walking into a postbox on the way home from work; he then drunkenly apologises to the post box. The second chapter shows Kenichi repeatedly getting late for school; and a prophecy that he and Yumeko Kawai will get married and have children together. The third shows poor Shinzo getting a stomach ache after eating too many ice creams. The fourth is about Shishimaru causing a minor earthquake with his loud snoring, and the fifth shows Hattori wetting his bed! Everyone, especially Hattori, is extremely humiliated; fortunately, Mrs Mitsuba realises that she doesn't want to be a writer.