When you quote me, please note that the first chapter was changed after I wrote the comment. In the first version, the mother only tells Paul that he’s starting to wear diapers at night, after which she goes on to put a diaper on the astonished child without any explanation.
Excuse me, but that explanation doesn't make any sense. The story could have started with Paul waking up in a wet diaper on Saturday morning, or you could have started the story on Friday night if you wanted to include the long scene where Paul gets a diaper put on.