Doyle’s use of the first person narrative voice allows us access into Paddy’s thoughts and feelings. The use of internal monologue allows us into Paddy’s private and often very jumbled thoughts.
This is an effective narrative device as the narrator sees things first hand and reports to the reader what has happened.
In some writing this can be a disadvantage as we only hear about events and people through the point of view of one person, which can mean that it is biased.
However, this is solved by Doyle to some extent by his use of a child narrator. Paddy - in his childish manner - relates what he sees without comment or judgement.
His observations are often innocent and matter-of-fact, allowing the adult reader to make their own judgement based on the facts that Paddy relates.