When the children taunt Boo by Jem's running and rapping on the side of the house and when they play their game of "Boo Radley," cruelly enacting Boo's life, and when they peep in the window, he does not retaliate although Mr. Radley fires off a shotgun blast. Instead, he gives the children valuable gifts in the knothole of the tree until someone cements it closed and later, after the shotgun is fired and Jem catches his pants and has to remove them in order to flee, the pants are mended and folded neatly on the fence with the same caring affection as when Boo places the blanket on Scout's shoulders.
Clearly, Boo Radley feels kindly toward the children and lives vicariously through them as a sort of passive parent. Through his small interactions, his kindness comes through. Then, when Jem is threatened by Bob Ewell, Boo realizes the danger. Forsaking his own safety, Boo risks personal injury to save Jem and Scout. His goodness and love for the children overcomes his personal fears of his father and of going out of the house. Thus, like a parent, Boo comes to their rescue: "Boo's children needed him."
Boo is an innocent person similar to a mockingbird and while the children have made his life hard at the start, he still goes out of his way in order to help the children and be their friend. He is also the reason that the children were saved from the evil Bob Ewell. While reading the story it is obvious that he is the mockingbird.
the children take interest in him,and who he is.they try to bring him out of the house even if thats just their curiosity talking.boo radley is lonely and he likes to see the children playing or walking by his house.their curiosity sparks off his friedly side and he starts leaving gifts for them in the tree.When Jem leaves his pants in boo's backyard fence,he folds them for him.Later when theres a fire at miss maudies house,he covers scout with a blanket to stop her from feeling cold.And at that end of the novel he comes forward with his final act of heroism.he saves jem and scout from bob ewell.
Boo Radley has always bin the innocent bystander but through all he does for jem and scout,we actually see thats hes a nice person unlike how people imagine him to be which brings out the theme of appearence and reality.
He becomes affectionate and attacthed to the children and those little acts of kindness are just events leading upto that last big event.
They bring out his good side which helps the reader realize that he is the true mockingbird of the story.