Boo (Arthur) mends Jem's pants after Nathan shoots into the air thinking that Jem, Scout, and Dill were a black trying to rob him. When the kids were trying the escape, Jem's pants get stuck on the barbed wire and he can't get them loose, so he takes them off instead.
Dill lives in Mississippi during the school year with his parents, but comes to visit his Aunt Rachel during the summer in Maycomb County, Alabama.
Calpurnia takes the kids to the black church (First Purchase) while Atticus is away on business.
Dill runs away from home because, although his parents are kind and give everything he could ever hope for, they are distant and never want to play with him.
Uncle Jack gets mad at Scout for calling Cousin Francis a "whore-lady" and hit him, but he soon finds out that Cousin Francis called Atticus a "n-lover"*.
*I am choosing NOT to use the actual word as it might be offensive to some people.