I think it is interesting that Scout has no close friends of her own age in Maycomb. There is not a single mention of any girl friends at school, nor does she play with any during her free time. She spends most of her free hours with her brother, Jem, and with Dill during the summers when he comes to visit. Otherwise, her closest companions are all adults: Atticus, Calpurnia and, later, Miss Maudie.
Scout is devoted to Jem, who seems to be perfectly happy whiling away the hours with his little sister. When Dill makes his first appearance, he becomes the third member of their triumvirate; he
... had been studied and found acceptable. Thereafter the summer passed in routine contentment.
When playing in the treehouse and "running through our list of dramas" became boring, Dill's interest in the Radley house and trying "to make him come out" became their prime interest. When Dill left for Meridian, Scout "was miserable without him" until she realized that school was just around the corner. Jem warns her that they will not be able to associate with each other during school hours, and she gets off to a rocky start with Miss Caroline, her first grade teacher. The rookie teacher tells Scout that she must stop her reading sessions with Atticus--a nightly bonding routine which Scout thoroughly enjoys--and Scout spends part of the class period in the corner after being "whipped" by Miss Caroline.