This statement about the giraffes is a logical fallacy called hasty generalization.
The boy thinks that if one giraffe was friendly to him, that all giraffes are bound to do the same - he is generalizing something that doesn't have to be correct.
Answer:
Rowling employs omniscient limited narrator voice, in which readers see what Harry observes, and know what he feels and thinks. They are, however, unable to follow what the Dursleys feel or think about Harry.
Ok so is this supposed to be a question or something?