Essays / "The curious incident of the dog...."; Why Christopher's findings are important? [4]

Im writing this essay about "the curious incident ofnthe dog in the night- time" book
And as you know the hero of the novel is Christopher
And we know he accomplished 3 important things. Finding who killed the dog, being able to go to London and found his mother and wrote a book

Why are these accomplishment are important?
I need some supporting ideas to these point

Another think. if you think this topic is not good topic please i would like your opinion of another one and ill see if its in my topic list, because there is 10 topic i could choose from

Thank you so much