Sid's Role as the Model Boy
The Adventures of Tom SawyerSid, Tom's half-brother, is the obedient, tattling foil to Tom's mischief.
increasing
Bearing strength in each event
decreasing
The Thread Betrayal

The Tattletale
The Discovery
Sid notices that Tom's shirt collar is sewn with black thread instead of white, exposing Tom's lie about not swimming. Tom vows to lick him.
The Clodding
Tom later pelts Sid with clods in revenge, but Aunt Polly scolds him. Sid's tattling establishes him as the "good" boy.
The Contrast
Sid's obedience highlights Tom's rebelliousness. He is a constant reminder of what Tom is not.
The Sugar Bowl Incident

The Broken Bowl
The False Accusation
Sid breaks a sugar bowl, but Aunt Polly blames Tom. Tom is punished unjustly, deepening his resentment of Sid.
The Silent Observation
Sid notices Tom's sleeptalking about the murder and reports it to Aunt Polly, though she dismisses it as dreams about the murder.
The Unreliable Witness
Sid's attempts to expose Tom often backfire, as Aunt Polly's love for Tom overrides suspicion. Sid remains a minor antagonist.
Early in the story
Early in the story