How do the kids’s feelings about the painter using their wall change throughout the passage?

At first, the narrator and her cousin, Lou, are pretty annoyed at the lady painting the mural on "their" wall. For years, this wall has been used by all members of the community; it's come to symbolize the strength and togetherness of that community for generations. But along comes this strange woman, from out of town, no less, who spends the whole day painting on the wall, making no effort to ingratiate herself with the locals despite numerous overtures of friendliness.
The narrator and Lou are determined to drive this stranger from their midst. They hatch all kinds of cruel plans which they hope will restore "their" wall to its rightful owners. They even come up with the bold—and criminal—idea of wrecking the painter lady's handiwork by spraying it over with graffiti.
Thankfully, nothing comes of this vicious little scheme. When Lou and the narrator return to the wall, hell bent on destroying the mural, they see a large, appreciative crowd gathered round. The painter lady has left behind a big, colorful mural depicting some of the greatest African-Americans in history. Not only that, but the narrator is amazed to see herself and Lou are also represented on this astonishing work of street art. In the face of such extraordinary talent, Lou and the narrator can only join with the rest of the community in standing before the mural in awestruck admiration.