How does Anna and Mo's relationship change over the course of the novel, Three Times Lucky?

Anna Celeste Simpson is Mo's sworn enemy; Mo has even nicknamed her Attila after Attila the Hun. The two throw jabs at each other any chance they get and in no way do they act friendly toward one another. After Mo catches Anna Celeste's mother being mean to her, she takes a subtle jab at Anna Celeste's mother. To show her appreciation, Anna Celeste, as a peace offering, gives Mo a few bottles for Mo to put her letters in. They are fancier than the bottles Mo usually uses.

Anna Celeste's bottles are representative of one of the concepts present in the story: nothing is as it seems. Mo thought she knew exactly who Anna Celeste was and that Anna Celeste would never change. Her act of kindness changes Mo's perception. The same could be said in reverse: Anna Celeste realizes that Mo wasn't just her sworn enemy, she was also a rising 6th grader, just like Anna Celeste, who doesn't like seeing people be cut down.